You don't need a VM to play that, the library it uses has been updated every time so just look for the version in XP/Vista and it will work up to even 10, but I admit, good memories with that game, used to play it in music class at school often, competing for high scores with my friends seeing how high we could go before the period was over, fun times...
4GBs of RAM have been supported since Server 2000, you are behind the times, XP recognizes up to 32GBs unmodded and 64GBs modded. It's not W7 with it's crazy support for 1.5TB RAM, but more than good enough lol
i gotta say, the steam deck isn't a bad deal, even if you get a used one, you have options to get it serviced and the parts are also available through ifixit