I'm not so sure if there's solid proof that Satoshi left out privacy stuff in Bitcoin only to steer clear of regulations.  In 2009, crypto and what it could lead to was pretty much uncharted territory.  Rules from government might not have been a main thing on his mind and  seems he cared more about creating a decentralized and immutable digital currency that didn't rely on centralized entity and couldn't be manipulated or faked.  Maybe those goals took priority over making payments impossible to trace.