The bigger "risk" is to altcoins because the entire altcoin market has been relying on Tether specially during bitcoin bear trends. For example we saw during 2018 (when bitcoin was dropping) that Tether was being printed at a higher rate than 2017 to satisfy the need of the altcoin market as altcoin bag holders were trying to escape the dumping altcoins but didn't want to go to bitcoin either because bitcoin was dropping itself too (that drop was also causing the altcoin bloodshed).
So if anything, when Tether disappears all those shitcoin traders have nowhere else to go but back to bitcoin and that increases the bitcoin volume and reduces the "drama" effect on bitcoin price too.
Clueless in your opinion there.
Altcoins don't depend on tether, most don't even have a tether market pairing.
Dogecoin is the most highly traded markets against lower priced altcoins.
People that actually trade in altcoins know this.
Also if tether crashes, who says traders will be able to move anywhere, the places that hold the highest risk from tether are the exchanges.
The exchanges all crash, and the people holding on those exchanges lose out, but this has no effect on network function unless the coin needs to be profitable to afford to keep mining, which bitcoin is the most at risk.
* Most altcoins cost less than a $1000 to run and maintain monthly, so they can more easily survive a prolonged price collapse, bitcoin can't! * Because it is not like you can run a multimillion dollar warehouse full of asics at a loss of a few hundred thousand just to keep bitcoin alive.
Neither will the majority if the price vs fiat crashes.
Miners pay their bills in fiat, not bitcoin.