As a small counterpoint, I am supposed to use Windows at work but I use Linux. I would say that I am a “very heavy” but intermediate Microsoft Office user. That is, while I am not expert level in Office, I have to create and consume multiple documents per day. I give ( or submit ) several PowerPoints per week. These typically use templates supplied by Marketing or others. I create and consume multiple Excel files daily which almost always have multiple worksheets. I must admit that I have gotten authoring Word files down to maybe one per week but I open 3 a day at least.
Of course, I do not actually use Microsoft Office most of the time. Most of the above is in LibreOffice. I spend a tonne of my day in Outlook which I use in a browser ( Office 365 ). If I am opening a document from an email, it will often open in Office 365 online ( in my browser in Linux ). So do I use Microsoft Office quite a bit but rarely author anything there. While I prefer Firefox, I use Microsoft Edge on Linux and most often that is where I have Outlook open. Sadly, I have at least 3 to 4 Microsoft Teams meetings a day. Teams and GoToMeeting are why I started using Edge. It is just a nicer workflow if Teams and Outlook are in the same browser.
Anyway, I have very little problem exchanging documents. I had to switch to default fonts that Windows users will have of course but that was long ago now. So, I would not say that “alternatives such as LibreOffice aren’t just good enough” is a fair assessment for everybody. If I was an expert user in any one app ( in Finance maybe ) I could see this being true but I bet most office workers could use LibreOffice just fine these days.
Outside of Office, most of what I use are web applications which work just as well on Linux. I use containers a lot and they work better on Linux. Linux is quite bit snappier on the same hardware.
I am just a datapoint though and the issues you raise are real. I would perhaps just be less absolute about it. Trying Linux can still make sense. Also, you can try LibreOffice on Windows before jumping all the way to Linux.