If you justify or make allowances for criminal activity for any protest, no matter how just the cause - you set a precedent.
The reason why is simple. The people protesting always believe their cause is just.
Criminal damage/assault etc no matter for what the cause is never acceptable and it shouldn't ever be excused, or allowances made.
Spot on. Tried to explain this the other day.
Same with the tactic of saying "oh it wasn't us" when things go wrong. BLM protests were not "non-violent", and claiming they were allows things like the other day to happen with the proviso of "largely non-violent" too.
Thus there's no accountability. This, again, isn't false equivalency, as obviously one was grander in scale than the other, but as you say one sets the precedent for the other, and one antagonises the other.
There's no such thing as a "good" riot.