My guess is one or more of the billionaires that Elon pissed off started funding a persistent anti-elon narrative, and that has shown up as bot farms especially on reddit. Then people who don't think for themselves started propagating it wherever they go... Because of how fun it is to argue on the internet and all of that.

It started as an anti Tesla narrative which was obviously paid for by the Tesla shorts, but this new supercharged anti Elon narrative ramped up when it started to become clear he was actually going to buy Twitter. So my guess is it's related to the interests of whoever was benefiting from the old regime at Twitter.