All hail the King
Special counsel Jack Smith and his team to resign before Trump takes office https://www.nbcnews.com/politics/justice-department/special-counsel-jack-smith-team-resign-trump-takes-office-rcna179928
No, that's not the precedent.
Presidents are absolutely not above the law. It's just that they don't really prosecute themselves, so other agencies at other times have to do it.
For example, Congress can hold presidents accountable for illegal behavior right away, and state prosecutors can go after them in civil court at any point. Clinton is the key example of that.
Presidents are never above the law. The tricky bit is going to the correct one to hold them accountable.