Very good PSA, and for that matter, don't even think to use most altcoins because most of them are also not decentralized enough or indeed, complete centralized. I dread to think of what happens if governments decide to freeze the few known clients and nodes running some coins.
Cryptocurrency that is created by a centralized entity (company, person) and not decentralized in technology will be shut down by governments at anytime. They are not different from traditional companies.
Bitcoin is different because the creator is unknow (what we know is Satoshi Nakamoto is the creator but it is the name on Internet space and no one so far is able to know where he lived). Moreover, the protocol of bitcoin makes it is a totally decentralized cryptocurrency.
Government can not shutdown bitcoin but as being said they can seize bitcoin wallets that are own by centralized companies. If you are customers of centralized companies that control your private keys, your bitcoin can be seized. The fault does not belong to bitcoin protocol, it belongs to wallet provider.