I doubt a government will go that far putting a person in jail just because he is using bitcoin. Here in our country top international CEX like Bybit or OKX are banned by the government but people still prefer using it and they find ways to access the platform. Same with bitcoin, people will keep using it with or without an intervention from their goverment.
I mean, we can imagine a world where that happens tbh. Regarding CEX, the government can also add a law that anyone accessing an overseas/banned exchange can be fined too. Whether it's feasible for them to enforce that is another question. If your government is so influential, there's a higher chance the exchange will comply if they ask for their customers' data. But if that does happen, there's also a high chance they'll just apply for permission instead.
At the end of the day, if you're not doing it publicly, not encouraging others to do the same, not having any influential position, I guess it's true that you won't get any punishment just because you use banned assets like Bitcoin (unless it actively destroy what your government is trying to do, like controlled digital asset, etc). CMIIW.