An interesting question, which I don’t know the answer to yet, is why.
How much was deliberate strategy? If the answer is a lot, it’s a greater display of cohesion and discipline from Antifa networks than most thought they were capable of.
How much was accidental? Or maybe a better way to put it, how much was individuals deciding on their own that they didn’t want to go (out of fear of being outnumbered, expectation that this would make their opponents look bad, something else) and how much was group organization? And to the extent it was organization, how much was person-to-person network effects and how much was instructions from leaders to others?