Random thought: Windows is largely successful because of Piracy
Windows as a software package would have never been affordable to individuals or local-level orgs in countries like India and Bangladesh (especially in the 2000's) that are now powerhouses of IT. Same for many SE Asian, Eastern European, African and LatinoAmerican countries as well.
Had the OS been too difficult to pirate, educators and local institutions in these countries would have certainly shifted to Linux and the like. The fact that Windows could be pirated easily is the main factor that led to its ubiquity and allowed it to become a household name. Its rapid popularity in the '00s and early '10s cemented its status as the PC operating system. It is probably the same for Microsoft Office as well (it is still a part of many schools' standard curricula).
The fact that Windows still remains pirateable to this day is perhaps intentional on Microsoft's part.
For private individuals and small institutions, yes, they would definitely use linux if windows was 100% impossible to pirate.
For corporations and bigger institutions, no, they would 100% continue to use windows just because of the control they can have on their devices, group policies, single sign on, and so on. It's possible to do that on Linux, but not as easily. They're already paying 15 dollars / month to microsoft just for AAD/entra/[whatever they call it this week] or even more to have office integrated with that and $200 for a permanent license for a single PC is a drop in the bucket
group policies, single sign on, and so on. It's possible to do that on Linux, but not as easily.
It is just as easy, if you have a sysadmin who knows what they're doing. Which is the case for Microsoft too, you need someone knowledgeable for the implementation and management anyway.
This is where Windows being "free" and everywhere comes in, everybody buys Microsoft without a second thought.
Linux is designed to be able to do group policies like that very well
Remember, Linux originates back from the terminal days, and the vast majority of servers run Linux. If any OS is made to function well in large organizations, it's Linux. Windows is popular on desktop for reasons other than better group policies.
When I was working IT in a place that produced transcripts - so we had loads of typists all using Windows and MS Word loaded down with a thousand macros - the IT department made all of the servers linux based, and all our production was stored on samba shares. The only reason they hadn't transitioned the entire workforce to linux was resistance from management.
I imagine there would've been resistance from users too, but all of the inertia was due to familiarity and had absolutely nothing to do with technical barriers. The entire IT team was frothing at the mouth to be free of Microsoft's arbitrary BS. Windows caused us no end of headaches.
In fact, because every typist needed a browser open at all times to research legal terms and other details, I had a number of people complain their computer was running slowly. For every one of them, I installed firefox and made it the default browser and told them they'd need to login to all of their online accounts again. Every single one told me I'd "fixed the computer" and it "works so much better now".