The screen size matters significantly. More specifically, what humans care about is pixel density. A 24 inch 1080p screen does not look the same as a 27 inch 1080p, which does not look the same as a 32 inch 1080p.
A 24 inch 1080p screen is perfectly fine. A 27 inch 1080p, you can start to see the pixels more clearly. A 32 inch 1080p IMO is unacceptably bad.
I would say the standard should be 1080p for 24 inch or under, 1440p for 24-27 inch, 4K for 27 inch or above
I personally run a 24 inch 1440p screen because I'm pretty picky with pixel density, and the monitor was relatively good deal.