So he did for himself because some personal revenge to the FBI. As stated in the news:

“I just called the mother of Ross William Ulbricht to let her know that in honor of her and the Libertarian Movement, which supported me so strongly, it was my pleasure to have just signed a full and unconditional pardon of her son, Ross,” Trump wrote on his Truth Social platform.

Trump called Ulbricht’s sentence “ridiculous,” claiming it was disproportionate to the crime. He went on to express frustration with the legal figures involved in Ulbricht’s conviction, referring to them as “scum” and accusing them of being among the same individuals responsible for the “weaponization of government” against him during his time in office.