For desktop computers, either Windows or Linux. Windows on my main computer since I rely on so much Windows-only software (MS Office, Many Games) despite the BS that Microsoft does to windows in new versions, but Linux has gotten way better lately, especially as it picks up new users as Windows declines. MacOS to me the worst of both worlds when it comes to lack of software support and corporate BS
For Mobile, definitely Android. Android is what I wish Linux was for Desktop computers; Loads of software you can get from many places, open source, and not locked down. It’s mainly the way it is because for Mobile OS’s, Microsoft was spending too much resources shooting itself in the foot with the Zune than to make the necessary improvements to make Windows Mobile to be competitive, and by the time they realized their mistake it was too late. iOS is such a pain in the ass for me to use due to how locked down it is, and while it has more software support than MacOS, its locked down nature and being mostly restricted to getting software from Apple means that several apps that I rely on (including a few apps not on the Google Play store) will never be available for iOS. I also like to see where every single file on my phone actually is
On desktop: Linux since late 1996. It is the only operating system that I can perfectly tune to adhere to my - often weird - ideas, and can run all the software I need. I’m a developer, mostly working on free and open source software, so Linux is right there to assist me with that. When I play games, I play them through Wine/Proton, have been since I started gaming on Linux some two decades ago. If a game does not work under Wine/Proton, that’s simply not a game I will be playing.
For portable gaming, I have a Steam Deck. Surprisingly, that also runs Linux.
My phone is running stock Android, and I hate it, because the way I function, and how Android imagines I would are not compatible, and the system does not let me bend it to my will, there isn’t enough flexibility built in. Like… I can’t uninstall a bunch of applications I’m never going to use, because my phone came preinstalled with it, and they’re not removable, unless I jailbreak it. Unfortunately, I can’t jailbreak it, because then my bank’s application would stop working. Which would be fine, since I don’t do banking on the phone. Except the application is required for mandatory 2FA. FML.
Thankfully, I can go days without touching my phone, so I can live with it being a piece of crap.
(The rest of my family is also on Linux: both parents, wife, and eventually the kids too.)
Probably is not going to make your phone experience much better but I followed this to disabled (not uninstalling) some stock apps on stock Android phones, works great and if you made a mistake it’s easy to rollback.
I did that, it did not make my phone experience any better.