Biden did commute the sentence of several other non-violent cases just last week or thereabouts, and Trump has been talking about Ulbricht for quite some time so it's not a complete surprise.
I guess the whole "murder for hire" thing excluded him from the "non-violent" category. But how that got tacked on seems very odd; the judge basically said "we didn't really handle it in the court case and it wasn't a charge, but it was mentioned a few times and it seemed basically true, so I included it in the sentencing". Like, ehh, okay?
To be honest, I don't really understand much of the logic ("logic") of the US justice system....
Including such evidence in sentencing consideration is not uncontroversial in the U.S. However, it can cut both ways, in that a judge can consider extenuating circumstances in a defendant's life to reduce sentencing. We want judges to evaluate cases and make sentencing adjustments where appropriate. So, I don't think I'd do away with the practice. The real issue is that this specific judge went absolutely bonkers far beyond the 20 years the prosecution asked for during sentencing (which was already very high) and sentenced Ross to two life sentences plus 40 years without parole.
Most of us who are happy that Ross was pardoned agree that he was guilty and deserved a jail sentence for the crimes he was convicted of. The only problem is the sentence was so wildly excessive for a non-violent, first-time offender. Compared to guidelines and other sentences it was just crazy and wrong. Ross has served over ten years. Now he's free. That's probably about right.