Without really intending to downplay your observation, I suspect that a sizable majority of Mac users searching for troubleshooting help don't google on such general phrases as "mac troubleshooting forum," but rather on specific keywords like "blue screen," "duplicate menu entries," etc.
When I'm looking for gadening info such as, say, how to cure onions, I don't search for gardening forums; I search for "curing onions."
That's not to say the more general hits aren't of value. People putting together lists of resources for Mac users, for example, may well search on such phrases.
