Thank you, I love exactly these kind of dives. Realtek makes absolute trash, they just happen to make affordable trash. The DP to HDMI chip was interesting, given most of these dongles provide hdmi I assumed the main usb-c hub actually did HDMI protocol translation internally, or I think alt-mode has proper hdmi support?
I go through these pretty quick too, they don't last long, I had good luck with the Startech dkt31chpdl and an anker which is an upgraded version of the one you "liked".
Overall I've found they mostly die, I have a Lention that seems to be chugging along, as well as 2 Lionwei's that haven't given me trouble yet, but mostly I've found Caldigit thunderbolt does the job reliably and for more than 6 months at a time.
Thunderbolt certification is considerably harder to attain than simply USB, so thunderbolt products generally are of better quality but more expensive.
If you don't care about the waste, I'd suggest going shopping on AliExpress with $10. The (USB) hubs you'll find won't be of good quality, but they won't be that much worse than the ones that sell on Amazon for $50+
Alt-Mode HDMI stopped at 1.4b. Everything now is DisplayPort Alt-Mode to HDMI. The translation is simple enough it can be done passively and components can fit inside the connector, meaning it looks like a simple cable.
Drawbacks are you can't get GSync, Freesync, or VRR. Also Nvidia's drivers only output 2.0 Audio over DisplayPort, so no surround sound.
Til. Shame, but DP is much better anyway. That explains why I can rarely get more than 1080p out of those anyway, only have a few good ones that go to qwxga.
Hdmi is such a disaster of a standard, I wish they'd just make new versions a different connector running DP, everyone would be happy, though the 5 people using the ethernet support would be SOL.
On YouTube I see guys make custom connectors for old ass computers with extinct connectors. Also as a child I made TV antennas out of paper clips. Cheap is king baby
Go read about UART (which you'll find in the Serial connector) which is still used nowadays as one of the standard peripheral inside microcontrollers (including in the cheapest $0.25 ones) and then go read about USB (you can start with USB HID, which is just the stuff for mice, keyboards, joysticks and the like).
Ditto for VGA versus HDMI.
You need a bloody software stack (which in dedicated adaptor chips is transformed by circuit generation software into a in-silico hardware implementation) for the newer stuff whilst the old stuff could often be done with a bunch of resistors and a handful of digital basic elements (no more complex than flip-flops).