https://www.joelonsoftware.com/2002/01/06/fire-and-motion/
https://www.joelonsoftware.com/2004/06/13/how-microsoft-lost...
Then you've got things like hiring concerns, $nextJob will want people with $nextTech on their resume, it doesn't matter if something is still technically supported because hiring people willing to work on dead platforms is a tough ask, moreso when the tech is a couple of generations old. This churn isn't happening in a vacuum.
Do you expect software to stand still for decades? Please show which other language stack comes anywhere close to this kind of stability because several of them (go, nodejs, rust) didn't even exist when .NET was first released and running critical systems in major companies.
You can still find COBOL and Fortran jobs if you want to avoid anything new, no need to complain about the industry moving on.
After winforms, silverlight, wpf, webforms and WinUI I don't want energy, I want to see them focus for more than 5 minutes. The only stable UI tech from MS with any long term support has been Win32 that came out 25 years ago.
I predict blazor will be quietly dropped (they won't actually admit it for 5 years), just like the others and you'll be forced to rewrite your software in a few years.