He wasn't sentenced for attempted murder, the sentence Ulbricht received was within the range provided by statute for the crimes he was convicted of. Judges have discretion in sentencing and they are allowed to consider the character of the defendant. The fact that Ulbricht attempted to murder people was demonstrated to the judges satisfaction during the trial and influenced her to sentence at the higher end of the range allowed for the crimes he was duly convicted.
The range allowed for those sentences is way too wide. Life without parole is nowhere near reasonable for hacking, money laundering, and drugs. Being within the sentencing range is meaningless when the range encompasses any possible sentence.