Did Satoshi ever mention anything about the taxing of Bitcoin?
I really doubt Satoshi ever saw bitcoin becoming this big, he created something with the mindset of a person of academics and he was just focusing on making something that he thought would be a lot better alternative to fiat money but in the end he wasn't expecting millions of people trading billions of dollars everyday on a trillion dollar market.
Definitely, Satoshi never expected Bitcoin will grow up this huge that even governments tend to admire this technology. Hence, He didn't see this coming and never thought about taxes. All he wanted to do is to Bitcoin become more complex and convenient payment transactions with of course no third party involved but seems there are still glitches like taxes.