Imagine a world where most mining was centralized and governments leaned on the miners to exclude transactions coming from addresses on the OFAC sanctions list.
You might be able to join the bitcoin network (run a node, hold your own keys) without asking permission. But if you had coins on that list you would be in danger of being censored.
You could say, 'Well, in that case, bitcoin is not permissionless.' But was it permissionless back when such miners only held 40% of the hashrate? Or when they had 51% and weren't bending the knee to the state?
Bitcoin is permissionless in that you can run any version of bitcoin you want to verify the chain and transactions you receive but I dont think it is permissionless when it comes to how you spend your coins. But I think censorship resistant is a better term because it also implies something about being free to move your coins around.
If miners start censoring certain txs, then devs will change the code (fork) and fuck them.
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