Pushing down alts is free.
Print tether. Buy alts. Sell alts at a loss, pushing them down.
Print more tethers. Rinse and repeat.
Because users USDT to just pump BTC is a bit conspicuous.
The only "stabilizer" to this market spiral of death I can think of would be alternative stablecoins that act counter to the market pressures of Tether&co.Essentially "countering money printing by money printing for the opposite spending purpose".