That said, I do think he absolutely deserved to be released, not because he didn't deserve to be locked up in the first place, but because he's clearly been rehabilitated and has done great work during his time in prison. All that considered, ten years seems like a not unreasonable prison sentence for what he did. I hope he'll continue to do good when he's released.
Those allegations were used to deny him bail and influenced public perception, they were not part of his formal conviction or sentencing.
He was convicted on non-violent charges related to operating the Silk Road website, including drug distribution, computer hacking, and money laundering.
Does this change your opinion of sentencing being well-deserved?
This standard is an enormous document, https://www.ussc.gov/guidelines which lays out the rules for adjustments. Evidence is admissible (by both sides!) for sentencing, with a lower standard of evidence and burden of proof, to either raise or lower the sentence within the very wide numbers of what the conviction was for. So the Judge in this case found that the lower burden of proof was met for additional violent crimes being committed (with Ulbricht's legal team having an opportunity to rebut), and that impacts the sentencing calculations.
Not a lawyer, but I have listened to US lawyers on podcasts.