Without meandering to areas that would be considered by many to be off-topic and only relevant to the Politics and Society board, the executive summary is that Trump wants to bring as many political prisoners home as possible. So nothing is off the table for him. No Russian criminal is too hardened for Trump to consider keeping in an American facility.
That being said, this particular man seems to be just an exchange hacker, so the prisoner swap isn't that unequal.
Why do you think that an ordinary professor is a political prisoner, unless it was his disguise for espionage? When a small fish is traded for a big fish, it usually means that the small fish is much more valuable than it seems at first glance.
The Russian in question is the founder of the platform, not some cheap scammer who hacked the naive. But people like him are obviously worth a lot in Russia, we already had the chance to see it recently when convicted murderers and saboteurs were welcomed as national heroes - although one should be honest and say that other countries also save their
"heroes", they just don't make a show of it.