We have about 30 projects in our solution (various in house xforms libraries, xlabs from source, tests, appropriate abstraction layers - it adds up).
Changing the xamarin forms version is an absolute bitch - basically kiss 1 hour goodbye.
And sometimes we need to do it due to bugs. Is there a way to do it for a whole workspace? I loathe switching it out as it takes forever, and if you just leave one project unchanged, you end up getting all kinds of crazyness going on.