Seems about right imo. And the poster Marius question is pertinent "what happens when you take $2.2bn buy support out of the crypto economy". That's only 1-1.5% of bitcoin capitalisation, or 0.4% total capitalisation ($522bn) today. And its not buy support, people sell bitcoin and other pairs to the convenience of USDT.
It's not like 'dollars' elsewhere. It's brand new money entering and buying. A lot of real dollars in daily volume will have been floating back and forth for years on end.
Tether is turbocharged buying power.
So no one buys Tethers? No one buys other coins? The exchanges tell a different story.