In each of your examples:
company -> government -> ban

In no instance can:
company -> ban
other than within their own company.

We get it. Banks have a lot of money/influence/lobbyists, etc.

But a bank cannot ban bitcoins.

Unless a bank has the power to kidnap people and put them in a cage after a socially accepted show of "fairness" they do not have the power to make something illegal. Only governments have such power.