Let’s say the PC doesn’t count and you aren’t taking into account backwards compatibility, emulation, online play, homebrew games, and the cost/availability of games.
I feel like I’d want to choose the PS3. Like the Xbox 360 it had a decent lifespan and a lot of games were produced for it. A lot of which are already some of my favorites.
The only things that would make hesitant are I feel like a lot of modern games are larger and have open worlds which I feel like that could be nice in the long run and many of my favorite games for the PS3 have been re-released.
I would say the Steam Deck is excluded. I specified against PC knowing people would either mention the Steam Deck or the Henry Cavill preferring PC meme.
I feel like otherwise Steam’s old Steam machines could also fit under the definition of being a console.
I suppose the unique portable hardware does make a good argument but the way I look at it game developers, for the most part, aren’t making games for the Steam Deck. They are making them for PC and I feel like that’s a big reason why I don’t consider them consoles. I also feel like that’s why devices like the ROG Ally and Steam Deck are considered handheld gaming PCs and not handheld gaming consoles.