Seems like, what I’ve found is that a terrorism adjustment can at most add 8 years to the sentence. So because he wasn’t even in the city at the time, he probably got something like a 16-year sentence for seditious conspiracy with the terrorism adjustment being 6 years, bringing the total to 22 years. It doesn’t seem like a slap on the wrist to me but he also wasn’t tried for terrorism directly. That’s a much harder-to-prove charge and the DA probably just wants to get him on what they already have strong evidence for.
That said I also believe we shouldn’t see prison as punishment but instead reform. 22 years should be enough time to reform him.