I've connected my Mac to 4k and 1440p displays and had no issues, in fact it was a pleasant experience.
Maybe if you noticed a lot of developers run Mac then you'd see their technical opinions are usually worthwhile.
Honestly you can use a Mac perfectly well without ever signing into iCloud + you don't get prompted to sign in ever really unless you click on a feature that requires iCloud like the iCloud tab in settings.
You can even use the apps like mail without ever signing into iCloud.
Yeah I think most people have experienced an iPad or iPhone but not a Mac so they assume it's the same walled garden. What they don't realise is Mac has been a solid choice for power users, developers and creators of all varieties for over 10 years, this means the community and app selection is honestly ridiculously good.
That's more of an architecture shift as opposed to we don't support it because fuck you, also Rosetta means most x86 Mac apps will be able to run on the m-series chips.
I've seen MacBook's last for 8+ years and remain performant.
The only place I've ever seen ads on my MacBook is in the App Store, the iCloud section of settings and on Apple's website, all of which it makes sense for the adverts to exist. Oh wait I may have seen one as a precursor to a YouTube video but sans ad-blocker that is standing regards of OS.
I personally love those features as a developer, I don't need every type of port pretty much just one would be enough in a perfect world we would use wireless to interface all peripherals and media items like cameras
This is just a clever safety feature so that those that don't need it don't accidentally mess around with things, if they're curious they can look up what it does.
They actually heavily target Developers with MacBook Pro, they even have a whole conference every year dedicated to developers.
Also I think fighting with macOS is the problem, there are a few walled off things however it's not nearly as bad as people make it out to be.
I find I have plenty of freedom on a Mac
Well you still have to check all the boxes, you pay for the license the same way you can study and take certain exams but have to pay for the certificate.