If a smart contract can automated the sale or not, then it’s still permission-less. Permission in the context of digital artifacts is be relegated to human decision making, not automated code. 

By the definition above, Bitcoin mining would not permission-less since it relies on permission codes for mine reward relea

I think there's a confusion between sovereignty and permissionlessness in the space. 

Sovereignty = you have complete authority (Can decide whether or not you pay royalties, etc)

Permissionless = removing a "human" authority/entity. i.e. transacting within the guidelines of a smart contract as you mentioned.

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