You get the idea
Yes, they are. It works fine. I'm using KDE fwiw. Icon scaling is one of the easily-configured features, especially on the taskbar. (The icons are all SVG, so why would you want to do anything other than native scaling?) Everything I use it for works fine. Maybe you should try it out.
If anyone is really bored, go try what this comment is suggesting. Run things at native resolution and change every system/application font setting to be 1.5x the default. Or instead just think about it for 30 seconds and just realize that a lot of UI is not text, and now you get 'normal' sized text with tiny images, icons, scroll bars, etc. and a lot of UI glitches such as text overflowing tiny buttons or clipping out of panels. The entire experience being suggested is hot garbage.