Where does the buck stop (literally) when someone in a country with failed/plummeting flat currency buys Crypto?

Something I was thinking about with Turkey's failing Lira, or places like Argentina: If a Turkish citizen is panicked at their cash devaluing and buys Crypto, the exchange obviously doesn't want to get stuck holding the bag, so they probably convert to USD (or buy more Bitcoin). But the place where they exchange between Lira/USD also doesn't want to get stuck holding the bag of a devaluing currency, so assumedly they want to do a swap as well.

But what is the ultimate resting place of this fiat, I am assuming the Turkish gov won't buy the Lira back, so at some point do exchanges just start saying they won't accept Lira (causing an even bigger drop in value)? Or do they jack up the exchange rate x2 hoping to cover their short term losses?

Sort of bizarre seeing all of this play out in real time, I would imagine many other countries will see their currencies fail in my lifetime, so I would like to have a better understanding of the dynamics at play.