OK, you got me there.  I made a statement that was overbroad--it's the main sections (B.D., A.D., Economics, Trading Discussion, Speculation) that have been overrun with spam.  I still find things useful in Exchanges, and I'm sure the mining section isn't bad. 

I think the reason I like Meta as much as I do is because it naturally draws people who actually care enough about the forum to talk about it--or to engage in its politics, as you stated.  From my experience some of the most capable writers tend to post there, whereas the illiterate shitposters flock to areas like Bitcoin Discussion.  You're right, it should not be this way but it is.  I think shitposters want to post in spam megathreads because they know their posts are diluted with 1000 other shitposts and therefore they won't get reported--and they're right!