In reality, he doesn't seem to have a deep, principled understanding of the issues of the "national security" apparatus (commonly known as the "deep state"). So I'm not optimistic, although maybe he's just waiting until after the election.
What Trump's administration is doing to Julian Assange is also quite evil (see Cassandra Fairbanks' reporting here - she's a very clear Trump supporter and yet is highly critical of his admin with respect to their treatment of Assange). It's not any more evil than what Biden or others would do, to be clear, so this isn't something unique to Trump, but we can certainly say that Trump has not shown any desire to try to do the right thing here.