Yes, some of it was organic, but towards the end of the bubble, folks were looking at tether printing and using that as a signal to buy / sell. People even during the bull run called out tether for being the biggest risk to crypto markets and understood that without this well-timed injection of cash into the crypto markets, the price would fall flat.

Given Crypto markets' propensity to scam, I'd be shocked if finex & co didn't engage in manipulation. Maybe not to the extent that the paper's authors claim - China, S. Korea, India all banned / tried to ban crypto and I think Chinese volume drying up was a major cause for the bubble popping.