I think Satoshi was not an A grade Computer programmer but he was a master at Cryptography. Satoshi had in-depth knowledge about cryptography, but he was not an expert programmer. His repositories are not organized, and even he didn’t use any classes there are just a bunch of functions performing transactions.
His imagination is greater than his skills, he created a secure platform and invented Blockchain Technology. Satoshi didn’t use conscious manner to write code but he used C++ functions very effective, and which shows he was good at C++. Satoshi might not be a full-time programmer but he was dedicated to his idea and somehow he completed this wonderful job.
Many big tech giants such as Facebook and Google had their first product full of bugs but from time to time someone finds bugs and comparing it to Bitcoin, it is an open-source repository and people can read his whole code.
Nothing is perfect.