I was replaying Xenoblade Chronicles on my Switch 2 and the whole time I was thinking about how this ENORMOUS, open world game originated on the Nintendo Wii, a console with only 88 MB of RAM.
With an OS the PC requeriments for that game under Windwos XP would have been like 256MB/384MB.
And I bet you that I could still fit an XP-era weather app or widget on top of XP and Xenoblade inside that 256/384MB of RAM.
Super Mario Brothers is none of that, but fits in a 40kB ROM and a few kB of RAM.
Atari 2600 titles are between 1 and 4Kb and have 128 bytes of RAM. Still enough for some quality entertainment back in its time.
They're pretty seriously limiting though when you actually look at those games. The GameCube/PS2 is probably the era where hardware was finally good enough to make the game you wanted.
Some of those games are remarkably fun and addictive though.
It's difficult to take an arbitrary spec and say that's 'good enough'. For some it's too much, others still want more. Depends on the kind of games you want.