Thankfully there is freedom of speech here and at the same time there is also a member that comes from a wide array of backgrounds (both geographically and with regards to mindset) and it helps shape the forum threads. Even though there is freedom of speech there are clearly restrictions in place, for example plagiarism and calls for violence are not allowed and those doing it will sanctions because moderators will take action. Strangely enough though, scams are not moderated and in that sense, freedom of speech here allows scams to operate. The latest of course is the promotion of mixer bans including URLs to their websites therefore freedom of speech has limits either in real life or in the forum.
Regarding the forum and those out there running similar websites, I think we all agree Bitcointalk is ahead by a long distance but (and I know some will disagree) in my opinion, other forums will increase in traffic and prominence over time because of the mixer ban. Mentioning those forums should be allowed without prejudice and in those forums they should also allow the mentioning of other forums too.
I do not see other forums as a threat to Bitcointalk forum. Bitcointalk forum has made a name for itself over the years and more people are joining the forum without restrictions. One benefit members enjoy from building the forum is freedom. Freedom to post useful contents from any forum that are free from plagiarism. Bitcoin is not in any form of competition with other forums, infact the teleport feature makes it even more easier for Bitcointalk members to go in and out of other forums without losing their membership in the Bitcointalk forum. If other forums place restrictions on adverts and promotions from other forums, it is them dealing with their insecurities. Other forums are still trying to gather traffic on their platforms therefore, bringing contents from other platforms means diverting the attention of their forum members.