Satoshi certainly made a lot of peculiar design choices, and one of them is the decision to use doubleSHA256 when even hashing is done.

We don't really know why he did this, but most speculate that it was done to prevent certain types of extension attacks. The reality is that this measure does not add any benefit, but when people proposed new changes to Bitcoin, found it was easier to continue the tradition, rather than convenience people. That being said more recent changes, stopped continuing the tradition and use single hashing, or with Taproot stopped hashing public keys all together(public keys should be public:)

Oh yeah I forgot to say, SHA256 was designed and patented(royalty-free) by the NSA in 2001.