Not so for the SQL Community
The MS SQL community has regular free events around the world and I have loads of help through Twitter from both MVP's and also some of the core architects of the SQL engine.
I think the problem the author is seeing is that there is no one MS group because the core technologies are so different. I personally don't want to go near Exchange or learn about it as it is outside my area of expertise. Whereas with VMware, I assume, everything within the VMware sphere is close enough that it makes sense to have just the one community.