Aren't you implying that the AS distribution is the reference to which all Perl module authors should conform? Why wouldn't it be the other way around?
I don't see why AS couldn't switch to gcc for their builds (theoretically speaking). At the very least, Strawberry will give _them_ something to build and test against.
In any case, Strawberry would give module authors a tool to test these things for themselves. The barriers to that are currently too high, in my opinion. Whether they will make use of that option is another question, but it seems obvious that they won't _without_ these tools.