There are many platforms that mixers can use to conduct promotional campaigns for their services, so I tried to find an explanation as to why they prefer the forums and insist on them, even though most if not all of them cannot be compared to the BitcoinTalk forum, and it can be said that they fail due to the lack of traffic on them.
The only logical explanation that I found is that all the rest of the sites refuse to place advertising banners for Mixers, knowing that as far as I know, there are no laws or legal conditions that prevent them from doing so (at least until now).
Because the community or forum is dynamic, people will stay on to read all the discussions compared to an advertising platform which will only show the platform site or banners, mixers will always have markets, and their clients will follow them on whatever platform they choose just to see if their service is still up to date the proof that they have a huge market is the amount of money they pour just to advertise their service if they can allocate huge funding then there's a big probability that they have existing and loyal clients.