Okay, so now that we're on a new page...
long stream of consciousness post ahead.
I don't really like macOS that much.
I think the software is kinda garbage.
I own 6 Apple computers and have used various versions of macOS on all of them, from Snow Leopard to current.
I strongly dislike Apple's tendency to deprecate its own hardware and software on a yearly basis, denying features to perfectly usable computers that can otherwise run its software with no issues.
I come from a professional IT background and dealing with macOS isn't really a big deal in the corporate space because everyone is on the same version, but trying to work with anything *legacy* macOS for the clients that I do freelance work for is a nightmare. Many of them are musicians and artists that aren't on the latest and greatest hardware and trying to support old installs of Pro Tools that they bought years ago while also finding old versions of Final Cut Pro and the Adobe suite, etc etc that will work on their computer after a reformat but which is ALSO simultaneously compatible with their hardware is a mess that I don't wish on anybody. Not to mention the fact that web browsers don't support their old OS versions anymore, either.
On Windows, most of this stuff would *just work* regardless of OS version or hardware, with very few caveats.
Looking past legacy support, I think macOS is a very aesthetically pleasing operating system and it's overall just *pretty* to look at --- but is just kinda meh to actually use. I admit that I really like the multitouch gestures and that throwing windows around with Expose is a lot of fun and that you really start feeling like a power user jumping between applications depending on the number of fingers that you're touching the trackpad with.
...but if you're on a desktop using a mouse, window management isn't as intuitive and having to install 3rd party software for features like window snapping is annoying.
On top of that, installing software is annoying as well. I don't want to use the App Store. I have to admit, I really like .dmgs. Back before I started using Linux and was exposed to package managers, most things were installed through .dmg files and I thought the idea of being able to either run a sandboxed version of the program from a mounted .dmg OR install it by simply moving it to your Applications folder was absolute genius. And in a lot of ways, it still is. It took me some time to understand at first, coming from Windows, but the fact that each .app file is actually a folder that has all of the program's files in it makes a whole lot of sense, and being able to install/uninstall things simply by deleting the folder is such smart design.
...but then there are edge cases where that doesn't always apply (Professional level software, mostly) and it can be a hassle to deal with those programs.
But I still think that a package manager beats installing .dmgs any day.
Fortunately, Homebrew exists for macOS but I don't like that a lot of software only has homebrew versions as opposed to native .dmg support. That sounds counterproductive to what I just said about package managers, but for some reason I don't trust the Homebrew repo as much as I would a native repo from Apple (I feel the same way about Chocolatey on Windows) and getting homebrew to work on older, unsupported versions of macOS can be a chore.
I don't like that I need to install Xcode to do basically any form of software development, and getting Xcode can be a chore as well. I don't like that it used to be paid-only back in the day and I don't like that it requires the App Store now. I don't want to make an Apple ID just to be able to develop software on macOS or compile certain software through Homebrew.
I also dislike how Apple hardware isn't as customizable. Ignoring the fact that their laptops have no user-replaceable components these days, Intel Mac Pros pre-trashcan were full desktop-sized workstations that had full PCI-e slots and, in theory, could support arbitrary user-supplied hardware.
In practice, the hardware they ACTUALLY supported was heavily limited to certain cards that Apple specifically provided support for, unless you could find a hacked kext somewhere which is incredibly sketchy, not guaranteed to work, and not something that I want to do. In addition, the way external GPUs were powered was through a semi-proprietary connector on the motherboard that was voltage limited and went to a proprietary connector on the proprietary power supply, meaning that you couldn't upgrade to a beefier PSU to use a stronger card.
Plus, Apple Intel hardware uses non-standard proprietary BIOSes that mean that you can't configure them outside of the OS, using an unsupported graphics card would result in no video output until the OS was booted (meaning no way to access any of the boot screens with an upgraded GPU), and going down the rabbit hole of finding Apple's test software to try and diagnose hardware issues that they don't publicly document anywhere since they want people to pay for AppleCare was an actual nightmare.
Basically, if an older Mac stops working it's practically e-waste.
MagSafe on laptops is wonderful and the fact that other companies haven't cloned it is unfortunate.
I imagine that macOS is great for people with iPhones and iPads and who embrace the Apple ecosystem, but I strongly dislike iOS, I don't use tablets, and find the experience of using macOS to be... fine. Just... alright, after a significant amount of customization to get it to not be so... macOS.
Ironically enough, I use Linux on all of my Apple computers these days. I daily drove a 2013 MBP with Ubuntu on it for years and although the hardware feel and build quality was top-notch, the weird internal Apple quirks it had made installation and driver support a chore compared to a similarly-specced non-Apple machine.
I feel like if they were less focused on trying to force their customers into a walled garden and used non-proprietary firmware, Apple could have dominated the market in terms of hardware sales to non-macOS users.
tl;dr: The biggest problem with macOS is forced obsolescence and Apple's tendency to nickel-and-dime its customers into paying for the latest and greatest software/hardware. Their hardware is really nice and pretty on the surface, until it suddenly isn't.