I can see China doing so, because , well, they're rather controlling of everything.
I can see NK doing this eventually (if it's even allowed there?)
As for others:
I think the point here is to try to reign in the mess that is digital currency, to look after their citizens, as they should be doing.
As it is now, it is far , far too risky for anyone to place faith in digital currency. I've said this before, and I'll maintain it until the day it becomes a legitimate payment source, regulated as are any official currency.
If I chose, say, to put faith in the stock market, and my stocks fell, that's on me, yes. However, that's highly regulated, meaning that the odds of something like what's happened with BC over the past few weeks, is somewhat unlikely. Not impossible, just unlikely.
The goal here I would say is protection. People are just damn stupid today, and need protection, as it were, from things like this, that can go sideways quickly.