The root cause is that Microsoft hired a bunch of UX designers to revamp Windows 11, but all of them are Mac users. They're basically copying the MacOS style into Windows, whether it makes sense or not. They don't even use Windows, so they're not eating their own dog food. To them, "success" is that it looks superficially "Mac-like", job done.
Like you, I'm getting fed up with these changes, most of which are objectively worse.
I also tried the "new" Outlook, and it was staggeringly bad. Not only was it shockingly slow, the UI got dumbed down and there's wasted whitespace everywhere. Essential information is hidden, and the whole thing looks like a PowerPoint presentation of what an email client looks like instead of an actual piece of usable software.
Then again, it fits the ongoing mess of GUI civil war happening in Redmond across Forms, WPF, UWP, WinUI, MAUI, MFC and of course one gets to put Blazor everywhere there is a Web widget, including the previous set of GUI frameworks.
Same applies to other commercial OSes, Google IO hardly brigns anything new that I care about for Android since several years, I already lost track of how many times they have rebooted background services or notification APIs.
The Year of Desktop Linux would be nice, yet even there I lost track of how many audio stacks, laptop support, distribution specific changes just because, and what not, has happened during the last 25 years.