They all say Bitcoin cannot be stopped, which of course, we can see in this case, is a complete lie.
If Bitcoin cannot be stopped, then why is Coinbase "stopped" by some regulation
Bitcoin as network is unstoppable, obviously. If you purely focus on what governments force exchanges and other services to do, then it's a different thing. It's not that Coinbase is forced to stop, but more that they consider complying with the rules that apply in Hawaii not outweigh the benefits of doing so. The only easy way to deal with the situation then is to simply halt their operations there.