If people will lose trust for USDT for some reason, then the price of BTC will skyrocket. Everyone will start to exchange USDT for BTC and it in turn will drive real price up. (people will pay more and more USDT per BTC just to get rid of it)

Meantime one can try and use bitUSD (only on bitshares platform for now) or SBD (this one is not bad but the problem is it is listed on exchange as SBD-BTC so you can't see USD value without calculating first)
I am mentioning them because there is real need for people to have some kind of USD pegged crypto, so it can be transferred fast between exchanges and maybe can point this out to some exchanges, so they will allow necessary changes.