I don't think it's a lag thing - decentralized cryptocurrencies are just hard for governments to stop. Similar how governments would like to stop people paying cash in hand and avoiding tax but have never really been able.
The answer seems to be that repressive countries haven't yet put in place effective mechanisms to be repressive with respect to bitcoins. But there's zero reason intrinsic to bitcoin to expect that to continue. On the contrary, since everything is digital the choke points are easier to control, not harder.
There are use cases for big money transfer and just "storing" money in BTC, not really for daily transactions.
The reason it was impossible, until recently, for an Iranian to open a bank account in Switzerland was not because of the Iranian governments, it was because the Swiss bank was afraid of running afoul of the US sanctions regime. Because those sanction have been lifted (at least for now) an Iranian can open a bank account in Europe, albeit they'll still have to go through a fairly extensive KYC process.
The thing is that restricting bitcoin is really hard.