>For sure, if you are dead-set on using proprietary software that is not available on Linux (or at least on Windows), then you may be blocked. However, if there is a port of the application to at least Windows, you can run that application on Linux using PlayOnLinux/WINE.
Full disclosure: I am a Linux bigot. As to the first statement, yes, I do have to say, sometimes someone is genuinely 'blocked' as you put it --- stuck with Windows for some essential proprietary application. This is however, in my observation at least, much less often than people think, the primary driver being as someone mentioned in a post above, a management mandate to use Windows where you work. Other than that, the cases seem to be very specific and limited--- a hospital's MRI software or something like that.
As to the second statement, Wine/PlayOnLinux is viable for some things, but very definitely not all. Even a VM is not a solution for every application or game, so I don't go too far down that road when I recommend Linux. The real answer is finding Linux applications that do what you need to do, and I've been able to do that almost all the time.
Heck, my wife runs Linux and doesn't even know it, nor does she care. She does everything she needs and wants to do and I don't have to worry quite so much about malware.