It's a bit like if the TalkGold forum banned advertising banking services

Anyway It's going to hurt the whole niche for sure and forums won't be the only one following this decision. For exemple, blogs won't allow purchasing advertising space on their website.
And scammers will make a lot of cash from it. Bitcointalk is considered having a high DA and with high PA and that's what bothered scammers a lot.
I know Theymos can say: "outside this forum is not my business". Yes, true, the matter is the forum and not the world wide web
As for promoting a mixer, it won't be difficult to bypass the change. The admin then will have to make more changes for a total ban because the quote below will only work 3 months about
Several people seem to be concerned that the current policy will be too disruptive/constraining. How about I make this modification to loosen it a bit: you can direct people to mixers by name (even in something like a "top 10 mixers" topic), as long as:
- You don't directly post their URLs.
- It's not a paid ad, and you're not representing a mixer.
Would this be sufficient to address the concerns?