Apple tried this, I forgot which year, there was a push to make the Apple TV a console. Arcade support, controller compatibility, it all shipped. You can plug in an Apple TV and pair an Xbox controller right now and play a surprisingly large number of AAA and indie games, from Resident Evil VIII to Slay the Spire. It was too little too late, though. Most games are played on phones, and the console market is falling apart. Microsoft seems to be pulling out, Sony is basically shipping locked-down gaming PCs with a couple of exclusive games. Nintendo is holding course more or less, but their main value propositions are simplicity and first-party exclusivity, and phones already ate the first half of that.

there is the steam machine but from my experience it is a matter of hardware drivers and support.

Steam Machine is GREAT. But it still has warts around controller support etc...

Also, a lot of AAA games do not work on steam machine because of aggressive anticheat and DRM, and those vendors don't provide Linux builds. No spyware, no game.

The software for the UI just isn't there for Windows machines. There have been attempts but it is always janky and you end up pulling out a keyboard anyway.

Devs are afraid of piracy so they like the walled garden. They don't want emulators running because then they have to compete with the 90s-2015 era which is the golden age of gaming, and their newer games don't stack up ( except in graphics ). Nintendo doesn't want to compete with Mario Kart Double Dash on the Switch 2.

Also: Modern PCs absolutely MOG the Switch 2 and Xbox. The games are all in the same engines and cross-platform anyway, so piracy ends up useful.

A pro device is going to be expensive. Non gamers won't buy it, let alone $60+ games.

Consoles come with a controller and enough storage to be usable for games. The largest Apple TV 4K is 128GB and it's really common for games to easily be 50+ GB or even considerably more. 100 GB is not even that uncommon anymore (e.g., Call of Duty, FF7 Rebirth, Baldur's Gate 3).

When Apple first launched the Apple TV game store they required games be playable with the horrible remote. Understandably even games that would have been fine on the hardware didn't bother and while Apple later relented and allowed games to require a controller it's still an extra purchase that's needed.