Not to take away from the great things happening here, but my impression is that the Room 21 Twitter acct and some of it's related accts are paying a company to get them followers. That would explain jump in followers you saw and the Rock on Festival feed having 179k followers, as well as oddities I noticed in the Room 21 followers list.
A while back I went through the Room 21 followers and saw they had lots and lots and lots of people with Turkish names far down in the follower list. I checked now and see all the followers at the top have a first and last name and their @address consists of the first name combined with the first few characters of the last name followed by a number. I mean they are are all like that, and none have a description for their account. The names also seem like they were made using an algorithm.
Not a big deal IMO but, giving John and others the benefit of the doubt here, I believe that Room 21 and one or two of the related feeds paid a company in good faith because they wanted to spread the word about their work and gain public interest. That paid company in turn used bad faith tactics to get the follower numbers up high. The followers are probably a combination of real people's accounts who became followers unbeknownst to them, and also fake accounts which are then set to follow Room 21 etc.
I'll add that I've had my own account made to follow other accounts without my knowledge, so I know it can happen.
I just wanted to share my thoughts on this since I've seen the high number of followers mentioned a few times by people.
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