I was in the Transformers RP fandom on Tumblr around 2011/2012. It was one of the things that got me to sign up on Tumblr. Me and a group of friends decided to join for shits and giggles, and because we were all big fans of Transformers. It could be really fun when you got a good RP going, and I met some nice people through there. But it could also be stressful.
The community I was part of split twice. Once before I joined, and once after. And there was drama too. In fighting from various personalities over what kind of content should be allowed and what shouldn't, and just arguing sometimes in chats. Also, one person was RPing as multiple characters (as many of us did) but was also pretending to be three different people within the RP. This nutjob would pick a fight as one person, then would turn around and act nice as another. She manipulated a couple of people.
I sorta just quit in 2013/2014 or thereabouts. Sometimes I think about joining a different fandom, because I see people RPing my favorite character and all I can think is "you're doing it wrong". But then I remember the stress and the effort and I just chose to not bother.
A good RP that flowed well was really fun though, and I do sometimes miss those genuine good threads I had going.