this is the first thing that came to my mind too.
because first of all they have been so much more vocal than they have been active. you can see the bigger blocks but not much else results. so now I think it is strongly possible that this was a social media sham from the start trying to advertise bitcoin cash more as a secure network that you can't attack.
The same guys did the same thing to bitcoin when the Lightning Network was introduced. Of course BTC doesn't need that kind of publicity because its already bigger than every single other coin put together.