My experience with the /r/startrek mods is that while they aren’t super transparent, their actions are usually justified.
A lot of people who get banned for “the wrong opinions” aren’t banned for their opinion, they are banned fro their aggressive behavior. Some people want a space where they can be loud and angry, and those mods don’t want to provide that space. I’m fine with that. I don’t like communities where I log in and the top posts are always people loudly making the same complaints day in and day out. Plenty of negative opinions and discussion were allowed on /r/startrek, as long as it was kept civil and constructive.
Just a few weeks ago we ran into this on tildes, a site not even dedicated to star trek. We had someone complaining about the /r/startrek mods, then going on to post really angry yet lazy comments about Star Trek that do not fit the Tildes community guidelines. They were asked to straighten up. It’s not about the opinions, it’s about the behavior.