The same I see Bitcoingarden forum looks quiet visitors and only a few active posts today means this forum can not be compared with bitcointalk and obviously the difference is too striking.
Well, yeah it looks like it, and yeah it's given, no forum can be compared to this forum, even the forum of bitcoin.com that was recently stopped its operation, i mean a year or two years ago i guess.
That's not an argument as nothing can be compared to bitcointalk. I think those companies(mixers) that want to continue to run their campaigns will find other way but even if they launch it with those alternative forums, they'd find little to no success there.
I'm sure one day they will find a good forum platform for mixer promotion.
Maybe or they'll keep their presence hidden from the clearnet and will have to stay on the dark shadows of the underground forum websites that can't be tracked(?).