I run a good chunk of that legacy software (I'm IT manager for a bank). There are alternatives. I'm not going to get 100% windows free, but I have already tested and started working on alternative deployment methods for specific pieces of software.
The most picky pieces I'll be using Windows Remote Desktop services. That way users who must use some of th eold windows legacy stuff can still access it. xfreerdp2 works great for connecting to RDS and it appearing native.
the hardest part for this migration will not be technology, but the users. My users are idiots. and the majority of them don't know how to use even their phones (I got an after hours emergency call over the weekend because some idjit locked out her peresonal iPhone)
All I know: More changes Microsoft is ramming through recently is making life incredibly frustrating. This mornings "major change announcement" is forcing banner ads through to outlook for "featured" outlook add-ons. They're pushing this out by July 30th, as "opt out". Meaning by default all my users are now going to automatically start getting this. of course there's an "opt out" but I have to go through and design a set of OCPS rules to block it. But Microsoft just says "go do it here" and doesn't even provide instructions on how to do it.
again: More microsoft developers getting paid to invent work for themselves that makes life harder for everyone of us admins. And they want us to have faith in Win11
I would be happy to see Windows destroyed in the corporate world, and would love to see FOSS OS taking its place. I would also like to see MacOS but that is not happening.
I wouldn't blame the "idiots" I have been using computers daily for most of my life and I still struggle with software problems. There is always something new and new way to do things, so I wouldn't blame people.
Apple used to be the company that "it just works" where any one can pick on the software and use it so much so they had 1 button mouse just so not to confuse the user. Today you need a pamphlet guide to learn all the touch screen gestures for iOS.