Strangely enough: Windows. Yes, I fucking hate Windows 10/11 for several laundry lists' worth of reasons, but you know what? At the end of the day, Windows is the only desktop OS that enables me to use my computer to do the shit I need or want to do. So long as that fundamental principle as a tool is not violated, I will forever be thankful for Windows regardless what criticism I might have for it.
I totally agree. Windows is the only practical desktop OS for most people.
Mac is not an OS you can use unless you buy the entire package, and then you have to live with many of its limitations. It absolutely sucks at multitasking (not that most average users care about this one, but anyone coming from windows will struggle).
Linux is absolute freedom, but that comes with the cost of having to do much more than install, plug and play. You need to be a computer geek, or you need someone else to fix things for you.
So as much as we are mad at Microsoft for deliberately damaging the experience of using what could be a joy to use, it's still the best at what it is.