Even if a government bans bitcoin that does not mean the the whole world is going to do it at the same time, so there is space for bitcoin to keep growing, also at some point people will realize the benefits that bitcoin brings and will force their governments to accept bitcoin even if they do not want it.
Actually we can see that already. There are countries that already ban bitcoin but still we have a healthy community because other countries are opened about allowing bitcoin to be transacted in that country. Do other countries follow to ban also this cryto?
And on the positive side, while other countries ban and restrict the access of it on that country, there are countries who did just not allow the use of bitcoin but even legalizing it that's why we can a growing number of merchants accepting bitcoin payments.