Does Microsoft even push or care about .net anymore? They seemed to move on after UWP and now that seems to be forgotten in focus of more web apps.

Microsoft care about .Net. It runs the Corporate world like Java

You have to understand that Windows comes from a separate division than .NET and they have no overlap. Microsoft isn't a cohesive company. .NET comes from the developer division (DevDiv) and UWP comes from the Windows division (now Server & Cloud). The Windows folks always hated .NET and the developer division has been lukewarm about UWP.

The Microsoft panel of this comic sums it up nicely: https://bonkersworld.net/organizational-charts

If it's like their previous ARM Windows attempt, existing native software won't work in any event because the entire platform is locked down.

Windows 11 ARM isn't locked down at all. I run it on a daily basis.

You can run any legacy Win32 .EXE on it that you want? I didn't know that. Good to hear if true.

It's actually kinda annoying once I started paying attention, as many software vendors just detect "Windows" and give you a x86/x64 installer, even when the company offers a ARM64 build that would presumably be faster or be more energy efficient. I installed a bunch of stuff that were Intel binaries without even knowing that I wasn't running native. But I haven't noticed any performance issues, and yeah everything just works.

In 2018 that lockdown situation morphed into "S Mode" which you can turn off in the control panel. The only trick is that you can't turn it back on. It's just that the ecosystem isn't there, both in terms of developers and performant devices.

Hopefully today's announcement is a turning point for that but atm windows on ARM is about on the same tier as a pre-carplay infotainment system.

Not really, plenty of Windows workloads are still about C++, in-proc COM and user space drivers, do require C++.

Not that WinUI really matters after all the mess WinRT/UWP went through, but it is basically C++ COM/WinRT with .NET bindings.