Public perception of what it means to be convicted has shifted with this election. Thiel of all people wouldn’t care if he is doing business with someone who is convicted, as long as they continue to make him money and push whatever agenda Thiel has.
"The President ... shall have Power to grant Reprieves and Pardons for Offenses against the United States, except in Cases of impeachment" [1]. Everything after that is, at best, case law.
> [1] The pardon would have put Nixon in a difficult position on the witness stand since he would not have been able to assert any Fifth Amendment privilege when questioned about his actions as president.