My experience has been that 1440p is noticeable jump in quality on desktop monitors but less so laptops. On desktop 4K is virtually unnoticeable, a high refresh rate, HDR, and OLED are far more noticeable.
For TV, I’ve found that it depends more on distance from the screen and resolution and bit rate of the media. I sit about 8’ from a 65” 4K tv and the difference between Blu-ray quality at 1080p and 4K is night and day.