Checking every single server to see if they actually chose accurate tags simply isn't possible. It's a security risk for our moderators and there are so many servers that it would eat up all our time moderating when we could be policing the site for other offenses that heavily affect user security/ability to interact in a fun/constructive wayt within our community.

Not only that, but just because a Factions server is also tagged as Roleplay doesn't mean it has to be one or the other. Perhaps a Factions server also considers itself role-play since its community may create back-stories behind their warring factions? Perhaps a Pixelmon server considers itself also a role-play server because players take the roles of trainers in the server? Not to say that some aren't mislabeled, but it's not as cut and dry as you appear to think it is and there are a TON to check.

By definition of the word, RPG is a role-playing game. Roleplay and RPG are interchangeable in this context, IMO, and don't really necessitate different categories for the same thing.

This is just simply impossible. Too many servers are uploaded to PMC each day to check for small things like type tags.

As for your last point, RPG literally stands for Role Playing Game.