I was forced to do this as my eyes have aged and I can't focus at 5K 27" at a reasonable distance, and can't read the text when I sit far enough back to focus. Hence why 4K 27" (~160 ppi) has become perfect for me.

Would be nice if Apple supported non-integer scaling so I could just dynamically resize everything (without the current technique and performance hit/blurriness of upscaling then downsizing).