Yes alternate platforms with good level of UX exists. But without content its no good.
YouTube - Peertube
Google maps - Organic maps & OSMAnd (open street maps)
Reddit - Lemmy (bigger is better)
For the others, maybe. But YouTube? It's strength is in the sheer amount of content. It's going to take a lot of time and resources to create and host that content on the fediverse.
Not necessarily. Nebula operates at a far, far smaller scope, with an emphasis on quality of videos over quantity, and every user is a paid user. If every user of YouTube was paying a couple bucks per month, they'd be making in the high tens of billions of dollars of revenue per year, several times more than they do with ads. Plus YouTube has a ridiculously huge amount of essentially worthless videos because literally anyone can upload a 10 hour video, so surely their hosting costs are higher per user than Nebula.
Subscriptions are really lucrative. Iirc most ads pay like 0.1-0.5 cents per view, so you'd need to watch an insane amount of videos to equal the cost of a $2 subscription. I could probably make a site that brings in money if I had 5 $2 subscribers and a half 100 medium quality vids. Start scaling that up and it can be really profitable while offering subscribers a fair shake.
I've been using duckduckgo for half a year already they've became quite good compared to Google search, Google maps alternative is any popular maps app just try what'll fit your tastes, but YouTube is certainly don't have alternatives YET just because libre alternatives though exist but not yet in shape enough (basically we need datahoarders who'll hoard and host whole youtube to libre alternatives such as framatube and others) for now we can only rely to custom frontends such as clipious, piped and others and custom apps of course
I started ditching google apps last spring and my “alternatives” are: bing/apple maps, invidious, and SearXNG. I self-host the last two to keep even more control of my data.
OpenStreetMap instead of Google Maps (OSM would be even better if more people used and actively contributed mapping data to it), no real youtube alternative yet (but see Piped/Invidious, Peertube, and Odysee), and there's plenty of alternative search engines like Duckduckgo, Brave search (has its own index), etc
there is no such "better" alternative. how could we compare a company that has been digging up their user data and built something with it, vs some community or even a solo developer who build something out of nowhere without collecting or selling data?
but, what are the alternative?
Google Maps
OpenStreetMap, is not as complete as Google Map, the amount of places won't be the same. but it's enough to help you navigating from a district to another district, and use much lower resource too
YouTube
Odysee, couldn't explain, think of it like YouTube
Rumble, couldn't explain, think of it like YouTube
PeerTube, a fediverse software where you can upload videos and do livestream, you own your data
Piped, NewPipe, PipePipe, Invidious are just alternative frontend for YouTube, its good if you are watching an exclusive content from their platform. But why do we keep letting YouTube has our data?
Google Search
wow, really?
DuckDuckGo, controversial, but enough
Brave Search, controversial, honestly aint using it
Searx, host it yourself, you own your data
and hey, why didn't you mention about the browser, mails, and many more?
There is firefox, tuta, and much more.