There's no generation that IS or ISN'T acceptable, it's all down to how clean and intuitive what's being displayed comes across after all these years, some games that went for a "realistic" look on n64 or even ps2 are painful to play now.
I have no issue playing Super Mario Bros on the Nes, or Crash Bandicoot on PS1.
For an example of games I couldn't play now... well old RTS games are a prime example, I don't think there's any RTS game before Age of Empires that I could find playable.








