Xbox 360. I still use it to play the Project Gotham Racing games, Burnout 3 Takedown, and some smaller downloaded games.

I still got my old 360 hooked up as well, fantastic console.

Every time I think I'm done with it, I find some hidden gem that I never played at the time. Just this year I bought and played Ace Combat 6, Stranglehold, and Enslaved, all excellent games.

Wii. Mainly Super Mario Galaxy 2 and a few other games that either have not been ported or were ported without motion controls.

I don't go back to old stuff. Old games are so depressing in their ugliness and simplicity. Ugh.
I feel like the PS4 was a kind of cut off point for me, where I didn't really need things to get much better than that anymore. PS3 and older though, nah.

I don't use older consoles anymore but I play PS2 games on my PC and on my android handheld (Retroid Pocket 5).

I don't have any of my older system hooked up anymore including the Switch 1 now that I have the Switch 2. I do have a raspberry pi with a lot of games, but I use that far less than I would have imagined when I got it. I haven't booted it up in over a year.

I don't have one, never had actually, only had a DS

But if I had one, it would be Game Boy Avance

Long after my DS has break, I use emulation it to play GBA games, it has been the case for the last ~15 years I think

This must be a trick question. PC is my main platform, so the age of games isn't really much of a consideration. Remasters and remakes are also an interesting consideration. There's also the matter of how many consoles I can fit under my TV.

All in all, I still play PS3 games quite often, as well as PC games from the same era. It's not terribly rare for me to play games as old as from the PS1 era and maybe a tad older as well though. In practice, I mostly play newer games, but I have a ton of older games in my backlog that are just waiting for the perfect moment - I most certainly have not abandoned old games.