It's all about choice. And choice, aka diversity, is great.

It's like not having to eat a banana if you don't like them and having the ability to grow the fruit you would love the most instead. That's also why I've now (in the last 5 or 6 years) mostly switched from Mac to GNU/Linux. This Mac Mac Studio I'm writing on right now is the last Mac I own and I see very little chance for it to be replaced by a newer Mac when time comes to replace it. I like the freedom of choice and to do what the funk I fancy on my computer. Not just what some designer at Cupertino (or some wannabe designer, at Redmond) decided I should be permitted to do.

Also, where is the standard between incompatible different macOS versions or different versions of Windows? Or between incompatible versions of the same apps running on those systems? I'm not saying it's wrong, nor that it's great, just that we should not neglect all those 'standardization issues' that exist in every single system. Marketing should not be blindly trusted — Imho, marketing should never be trusted, and not even listened to but that's just me deeply allergic to bullshit ;)