Patents can only be made on something that is not public knowledge.
If Satoshi had patented the idea before releasing Bitcoin, that would have worked (probably)
Years later it is stupid to talk about patents.
Yes it is stupid, nevertheless corporations especially in the United States patent all sorts of ideas that should be should not have been granted a patent. This is because the US patent system is broken. The EFF has been dealing with this issue for years
https://www.eff.org/patent-busting