I think the UI is very elegant, and some of the software is fantastic. I use Omnigraffle and Omniflow for design work and tracking my agenda items. No complaints whatsoever.
I hook up an external monitor, and maybe the OS isn’t completely responsible for this, but I get buttery smooth 144hz. It’s joyful to work with.
Everything just works. I don’t have to solve 10 other problems to solve the problem I actually want to solve.
I enjoy the customization and don't mind the occasional hiccup that needs some searching and wiki-ing to navigate. Finally, I guess I'm lucky to have used devices with very good compatibility out of the box so I've never had to fiddle too much to get things to work. I don't really have any reason or incentive to look elsewhere at the moment.
I like windows because I like portable applications. Since I'm forced to use it at work along with Office I like autohotkey and VBA because of the ability for automation. I wish there was something, maintained, like autohotkey for Linux. I know there's bash but with autohotkey I can automate most software I need to use day to day.
Something more esoteric: TempleOS (https://templeos.org/). I used it a few times years ago, very weird but with some interesting features (shell JIT'd all commands).
When something gets messed up I can read the source or just rip it out and replace it (or worst case, re implement it myself.) I almost never end up "negotiating" with my computer when I want it to do anything now.
I love the fact that I can customize absolutely everything. The AUR (Arch User Repository) is also amazing and has probably every installable package on earth.