There are plenty of supposed Steam Deck killers available in the portable gaming space, from the Asus ROG Ally to the Lenovo Legion Go and all the Ayaneo and ONEXPLAYER devices in between. But none of them have managed to outright slay the dragon that is the mighty Steam Deck yet.
Why don't tech reviewers every talk about gamescope? Gaming on PCs has always been finicky because PCs have to serve so many use cases at once and games often have to compete for resources. Gamescope completely circumvents all of this overhead by being solely meant for the purpose of gaming. It's the closest you can get to a "PC Console". Third parties can never make something like gamescope for Windows, Microsoft themselves would have to ship it and maintain it.
Why don't tech reviewers every talk about gamescope?
Because tech reviewers only read spec sheets and call it a day. They usually get the product for free and use it for a day or two, which is not nearly enough time to make an actual review of the product.
I don't get it. I'm not a gamer but I played tons of video games in my life and never owned a video game console. For me video game is just software: you install it, you run it. Why would it be finicky on PC? Why would I need dedicated machine to run it? I don't need dedicated hardware for any other software I run. If anything it's the consoles that are upgraded only every couple of years so there's always some new games that push their limits and are 'finicky'. I've been told that the new Zelda doesn't run great on Switch for example. For me consoles are a limited machine people put close to their TVs that make playing games a bit easier (UX wise) and more comfortable . They are like DVD players for games: I can watch movies on my PC just fine, having dedicated player close to my TV just makes it a bit more comfortable (well, now I just use Netflix but you get the point).
It's the principle of "do one thing and do it well". There's nothing wrong with running games in a desktop but there are limitless ways of customizing a PC and it's impossible for developers to account for everything. It would be nice if you could just write some code and have it work flawlessly for everyone's setup but that's not how it goes. For the use case of the Steam Deck where you are dealing with a low-TDP gaming device it makes more sense to have something like gamescope which can just cut out all non-gaming processes entirely. Maximize performance and battery life with a nice interface to boot, and the desktop is still there if you need it. At the very least it makes troubleshooting super easy when stuff does go wrong because there's very few external things to factor in.
I totally agree, consoles a better for simply running games because the entire UI/UX is designed to run games. But it doesn't really make them less finicky. There are still separate build with separate bugs. Cyberpunk was buggy on PS5, right? And with PC you're free to upgrade to whatever specs you need. With consoles developers have to try to adapt their games to fixed, sometimes years old specs and the results can be not great (like with Zelda).
The point is that a PC has a million possible configurations that can affect performance. A pared-down environment, like gamescope, cuts down on most of the software-side issues that a PC deals with.
Yes, just installing a game on Windows and running it is pretty simple, but these days lots of games have anti-cheats which can be triggered by other software running (or even just installed) on the computer. Windows on its own has a ton of overhead due to all the background and telemetry processes always running.
A console forgoes a lot of that background stuff, and limits the hardware compatibility issues by being a fixed environment. Your game only needs to run on one specific combination of hardware for each console it's released on. In that sense, it is a lot less finicky than running it on a PC.
You are talking about hardware deficiencies more than anything, you can get those on PC too if you just run low-powered hardware. I'm more talking about bugs. Maybe it's changed since I used Windows years ago, but I remember having issues from time to time with PC games. Crashing, weird behavior from alt-tabbing, some games just running at low GPU usage for no reason even though framerate is uncapped, and various glitches. There's a reason there has been a growing interest in sandboxing for software with docker, etc. Software is deterministic, if you give it a consistent environment it will do the same exact thing every time.
I think a good point on this actually came up in some of the ROG Ally reviews.
I remember one of the reviews compared Stardew valley on deck vs Stardew valley on the Ally, with identical settings. The Deck used around 7-8w, and the Ally used 17-18w, with spikes over 20w.
The reviewer ended up opening task manager on the Ally, and by force closing a bunch of background processes they were able to get the Ally down to 12-14w. But even with manually closes processes (which is unreasonable to expect users to do), he is wasn't able to get close to the power draw of the deck. This isn't even considering that people tuning gamescope and power tool settings on the deck can get it's power usage way lower, down into the 4-5w range.
Some of this power draw disparity may be the hardware, I've heard the deck hardware is more power efficient at low power than the Ally's. But it's undeniable that running windows seriously hurts battery life, and makes windows handhelds inferior to the deck for low power games.
PC is always a bit more complicated to use than a console. You have to deal with minimum requirements, graphics settings, drivers, troubleshooting, and such. I view PC as platform that takes more effort, but can give the best experience when everything's right.
Newer games that run too slow at the resolution you would like them to run at (you can render games at 720p and play at 4k)
Very old games insisting on running in a tiny (like 320x200) window (ie. xrick).
Games and applications who insist on running full-screen with no option to make them appear in a window if a window is what you want for a particular game or application (many scene demos will only run full screen at your current resolution).
Running older, non-widescreens games that do not support borderless fullscreen on Intel graphics with a desktop/external display (this is because Intel graphics do not support the --set "scaling mode" "Preserve aspect" xrandr argument on desktop/external displays)
Interestingly, Gamescope also provides a way to independently set max frame rate for the game when it is focused and unfocused, you could set it up to something really low when unfocused. Also interesting is the upscale options, you could use integer scaling for those old games, or force FSR on any title (although results can be mixed because the game UI will also be upscaled).
Gamescope becomes a very interesting option when you use it on a machine that doesn't have easy access to a keyboard and mouse, like a handheld, a "consolized" PC or even a "normal" PC that double duties as a "console" (playing games on a couch, despite using a desk for normal usage)
Like, I remember a friend of mine saying he had trouble running Sonic Generations on Windows because depending on what he was doing, he was either playing it on a monitor or on a TV. The Game for some reason detects that change and throws a fit, asking the user to reconfigure its graphical settings. Gamescope can lie to the game and force the game to see an arbitrary resolution.
I think there is an argument to be made that if you want to develop a game, for example, for the PS5 you can rely hone your game to the PS5 hardware and it could be extremely stable. This is not possible for PCs because PCs do not have fixed hardware.
However I think this was true in the olden days of the SNES where games where not glitchy compared to DOS gaming where hardware compatibility was all over the place. You can see this on YouTube channels like LGR where finding a compatible sound card is a challenge.
But like you, I don't find that this is still true for modern PC gaming.