While Styleforvm has undoubtably increased the popularity (and possibly cost) of a few "artisan" (I hate that word) providers, the creep in material prices and labor costs are primarily to blame IMO. In Italy, for example, the CPI has gone up nearly 4.0% since 2008, tax law is more rigidly enforced these days, etc. in the same time period wool has gone up nearly 25%. Cotton decreased this year but spiked last year.
I am not sure the 50 or so clothes nerds who regularly frequent this site can take credit for price increases anyway. Drakes was expensive well before SF - I paid $125 for a Drakes tie back in 1997, I think. Chan was getting rich off of HK expats in the 70's, before William Gibson even invented the term "cyberspace." His prices have gone up as his popularity increased, but I'd argue that's a general Internet - and not #menswearweb - phenomenon, caused more by the easy flow of previously inaccessible (or at least difficult to find) information.
I can't speak for Liverano as I know nothing about the shop, but again I thnk it's probably the marketing prowess of the Armoury guys, and not the forums, that have helped goose his popularity.
We forumites give ourselves too much credit, I think. if anything, i think the most we can take credit for is mucking up small shops with a temporary, but finite, deluge of orders (The Great Ambrosi Pants FlameWar of 2011 comes to mind). Any provider that jacks their prices based on the temporary rush resultant from the lemming-like habits of the SF crowd . . . well, that provider is going out of business. After all, how many pairs of pants or bespoke suits can the 5 real bespoke-ballers on SF actually buy?