I reckon what the author is saying however one can solve the problem of MacOS not picking up the proper scaling. I had to use a tool called SwitchResX. My Dell

I reckon what the author is saying however one can solve the problem of MacOS not picking up the proper scaling. I had to use a tool called SwitchResX. My Dell 25" monitor has a native resolution of 2560x1440. You don't want to use this native resolutions as everything gets too small to comfortably read/work. Had to input 3840 x 2160 as a 'scaled resolution' to get 1920 x 1080 HiDPI which gets you a sharp retina like experience. To be honest everything is a tad too big now but SwitchResX does somehow not save any other scaled resolution for my monitor (UP2516D / U2515H).