Windows 7.
It was the peak of windows.
It was slick. It was fast. It was stable, and it was super easy to use. Never had a single problem with it, and unlike past windows OS’s it didnt require regular reformats to clean house for stability.
Unfortunately its dead now, and Microsoft abandoned that approach and switched to a slow burn approach at walled gardening.
I use Linux now, have been for years, because I saw where microsoft was going when Win10 was in previews, and there was no way I was going to be part of it… So I jumped ship as soon as EoL was announced for Win 7
I use EndeavourOS. I like pacman and AUR, as well as the fact that Arch-based distros are well-supported by most software. I’m too much of a noob/too lazy to setup an OS without a GUI installer though, which is why I prefer Endeavour over Arch.
Mac OS. People say it costs more, but I am not paying for a hardware and then some software that tries to make use of it. Instead I’m paying for a well thought out product that just works.
Mac OS
It’s pretty, functional, and has unix underneath so I can use it the way I really like to.
plan 9
I don’t actually have the patience to run it, mind you. But it’s definitely my favorite in principle.