It’s hard to find a bank to take your money, since you’re something that rhymes with money laundering. Tether had a bunch of money stolen from them because the money launderer they used turned out to be a crook.

It also takes a long time to get this going and there are moderately high costs to a minimally viable financial entity (reporting, compliance). A few years ago they only had a couple billion which makes it hard.

And all of that sets aside the allegation that tether has been printing tethers it’s entire life — that it’s basically never been fully backed by dollars.