Charges were dropped because of illegalities committed in pursuit of him.
He wasn't the only one who was part of that group though.
Did any of them get any time?
They were also several other crimes committed after the fact by the group post-1973's charges being dropped due to the events you mention.
In November 1977, five WUO members were arrested on conspiracy to bomb the office of California State Senator John Briggs.
Mark Rudd turned himself in to authorities on January 20, 1978. Rudd was fined $4,000 and received two years' probation.[24] Bernardine Dohrn and Bill Ayers turned themselves in on December 3, 1980, in New York, with substantial media coverage. Charges were dropped for Ayers. Dohrn received three years' probation and a $15,000 fine.[24]
But were the BLM activists the ones who did the violence or was it adjacent groups such as Antifa battling the Proud Boys? And, of course, opportunistic looters with no particular politics.
I think the opportunistic aspect is one that would apply to people involved in Jan 6th as well.
Like this guy:
I could be wrong, but he doesn't strike me as a guy who sincerely thinks he's involved in any type of serious effort to overthrow the government, and looks more like the kind of guy who's "doing something for the likes".
He got 3 months in prison and a year of probation. To put that in perspective, that's almost identical to the sentence of Matthew Banta, Antifa leader who went by "Commander Red" who was arrested for bringing a flamethrower to a Wisconsin protest (and that's while being out on bond for a previous incident involving pointing a loaded gun at a police officer at another protest)
To be clear here, I'm not trying to defend any of the idiots at the Jan 6th event...I said they were idiots then, and that feeling still applies today.
However, if "lack of faith in our institutions" is the sentiment that's stirring up these kinds of bad actions, I don't think that sentiment is remedied by a justice system doing things that are coming across as looking biased.
I think the media and certain politicians have 'blood on their hands' for some of this too. Even if one could make a reasonable assertion that BLM/Antifa activities "weren't as bad", (I think one can make that assertion in terms of nefarious intent and what they were aiming to achieve, no so much on the property damage aspect), there was a reasonable critique that they were being handled with kid gloves (with politicians and pundits either outright defending those activities, or dodging questions with answers like "well, it's not even really a group, it's just an idea")
And it leaves some people seeing it as hypocritical when those same politicians/pundits suddenly adopt a "tough on crime/harshly punish anyone who presents substantial public safety concern" seemingly out of the blue.