I've had some android handheld devices in the past, but there were always some issues with them. I also tried controllers for my phone, but it wasn't really worth it. I do know there are some better handhelds out now.
So couple of years ago, I got a Steamdeck, and that hit the sweet spot.
But in the end, both Linux and Android handhelds are capable of emulating a lot. Linux however, opens the door to pc gaming thanks to proton.
It all boils down to your budget, and what it is you really want to do. Steamdeck is pretty much the best price/quality you can get, but if you only want to emulate up to Playstation, there are plenty of android devices on Aliexpress that can do that for a couple tens of dollars.