This is a tricky situation indeed.
We've created quite a few precedents in the crypto world.
The interesting part is, people were generally told: "not your keys, not your coins". After Hf23 on Steem, what should they be told?
The solution is rather interesting too. Trust an exchange to do the right thing. So a centralized, "not your keys" entity, rather than a blockchain mechanism. Granted, Steem is a hideous example of a blockchain right now, 100% centralized and transferring people's funds without consent. Chinese Communist Party would be proud.
You mentioned throughout comments a metaphor that each country makes its own laws.
Where you are wrong in the metaphor is that another country or even a citizen cannot dispute these laws. For that there are International Courts. Bittrex plays the role of an International Court right now. Unless they choose to pass the hot potato to a different Court, one outside crypto world.
It's certainly something I thought of but I'm already overcomplicating this issue.