It does not cease to amaze me how bloated Windows is (compared to any Linux out there, anyway), and how it gets more bloated with each update.
Windows starts bloating when you apply updates. It keeps a lot around to facilitate rolling back updates if needed; this gets cleaned up over time but it can be an issue on a small disk. There’s ways to get the size back down (while sacrificing the ability to roll back updates that you’ve applied), but you don’t regain all the space.
I get the feeling the Windows Update mechanism is a large legacy mess that is stuck having to account for corner-cases that have built up over time. Microsoft are improving it; I think it’s just a really big engineering task that they’re having to slowly work through. I vaguely remember something about the way Windows handles overwriting open files in-place which makes this worse, but I can’t remember the specifics off the top of my head.
I get the feeling that Windows itself is a large legacy mess that is stuck having to account for corner-cases that have built up over time. Of course this facilitates its impressive degree of backwards-compatibility (one of its most desirable features), but still.
I really think the amount they've improved Windows under-the-hood over time is impressive, especially taking into account the constraints they've had to work within.
On a related (though somewhat tangential) note I must say that I think MS tying WinRT (which as I understand it is the clean rewrite of the Windows API) to the Microsoft Store initially was a massive mistake. I still don't have a clear, confident impression of where I can or should use WinRT, even after all these years.
It was a corporate laptop, so maybe the problem exacerbated itself to that level due to frequent patches the employer was pushing.