The difference between my 27" 4k and 1440p screens is still quite obvious and I don't consider myself particularly sensitive to these things.

For rendering of text/video even an underpowered integrated gpu can handle it fine, only issue is using a bunch more ram.

For reference my very underpowered desktop AMD igpu on 3 generations old gpu architecture (2CUs of RDNA 2) only has trouble with the occasional overly heavy browser animation