This is where disinformation/misinformation comes in to affect a narrative along with people not taking the time to understand how things work.
With regard to the robbery conviction, he was sentenced to a minimum term of 6 years, 1 month. That is the highest minimum term he could legally receive for a robbery with a dangerous weapon conviction under North Carolina Structured Sentencing absent a finding of a statutory aggravating factor (which can be found only by either the defendant’s admission/stipulation in court or by a jury beyond a reasonable doubt, if one exists at all). The sentence he received also consisted of the highest possible maximum term of 8 years, 4 months. (In NC, you go into prison facing the maximum sentence but you have the opportunity to work it down to minimum term— and no less than that— upon completion of rehabilitative and vocational courses, through doing jobs while incarcerated, and by avoiding too many/certain kinds of disciplinary infractions).
As for the other arrests, most of them were for misdemeanors, including things like misusing 911 and disorderly conduct. Those are not charges that anyone is going to sit around in jail for. I also believe that the “14 arrests” referenced are actually referring to 14 charges vs. arrests. In other words, he wasn’t arrested 14 separate times. He was arrested fewer times, and some of those times he faced multiple related charges.
As for the assault charges, they were misdemeanors. If you have any familiarity with how things generally work with those types of charges, the prosecuting witnesses typically don’t want to have anything to do with charges after the arrest. They frequently duck subpoenas and don’t show up to court if they are served with a subpoena. I cannot say for certain any of that happened with his assault charges, but I do think it is very safe to assume that that is exactly what happened. In my 20 years of experience, it occurs much more often than not.