This article claims that discussing the social engineering programs based at the Tavistock is banned on various internet forums.
Keen to get empirical data, I posted this to r/conspiracy_commons. Sure enough it vanished without a word.
https://mirrorsoftruth1.blogspot.com/2019/01/tavistock-institute-for-min...
Conduct your own experiment! Post it to one of the forums mentioned and see if it disappears :)