I've been playing since the NES and despite being from a low income family I had the luck of being able to play and own many consoles over the 3 decades of my life, plus some pc.
If you ask me right now? Resident Evil 4 (2005).
A before and after in gaming, to this day still extremely fun to play even for casuals but 20 years ago it was THE masterpiece. And everyone took notice of it, everyone played it, even players that didn't cared about resident evil. The gameplay was so good that it got photocopied by everyone right after in the action genre.
Arguably the last big innovator in videogames minus Minecraft and... PUBG (Fortnite did it better I know).
Try to NOT pick your favourite game, that's a different thing.
100% agree. SMB3 on NES just had so much more stuff going on compared to SMW on the SNES. Mini games galore, secrets up the wazoo, and the muthafuckin' SHOE. For reals using that bad boy was like stepping into a goddamn Gundam.