No, it's just hard to advertise them. Groups often offshoot specifically because they disagreed with moderators of the previous group. The new group will want to attract users from the old group, but the old group's moderators set up bots to auto-remove any attempts at sharing the new group.

I linked the point in the talk where I discuss this, but I can share an example here too. r/LibertarianUncensored is 2,000 members and stickied this post [1] explaining shadow removals occurring on r/Libertarian which has 500,000 members.

If you bring this up on r/Libertarian your commentary will be removed and you'll either be banned or shadow banned. Both make it impossible for you to share what's going on with users in r/Libertarian. Meanwhile, moderators there publicly deny that anything untoward is happening [2].

Maybe some day r/LibertarianUncensored can overcome its userbase deficit of half a percent, but it's obvious that shadow moderation is helping to maintain r/Libertarian's domination.

Other groups that skew younger, for example r/Overwatch, may already be familiar with Reveddit and thus have a better chance at challenging mod biases [3].

[1] https://www.reddit.com/r/LibertarianUncensored/comments/uotv...

[2] https://archive.ph/O0GN8

[3] https://old.reddit.com/r/Overwatch/comments/ye16uv/this_subr...