There are pros and cons, the violence and damage done in the French protests also make it easy for the rightwing to shatter solidarity among left and center voices. These protestors take the narrative the rightwing wants to push about the left and immigrants hook line and sinker without reflecting on the consequences of that, which is very very very very dangerous.

Rightwing fascists want nothing more than this to become a fist fight, it is the only environment their shitty politics can survive in because everyone is too distracted by the violence to actually interrogate what each side is saying and determine fascists are violent and full of shit.

You can criticize a protest like No Kings in the US for being wayyyy too deferential to the status quo, but you can also on the flipside point out that everyone who goes to a peaceful mass protest leaves knowing they are in the majority, and that a vast diversity of people have arrived at the same conclusion and desire to exert their will in a collective fashion that no significant percentage of the society resists in a rational way even if the power structures do.

Once you start throwing bricks at the cops and burning everything down you cut the potential for solidarity into two opposing sides which isn't so say that ACAB isn't true or that the pearl clutching around property damage isn't insulting given the human suffering the protests are meant to illuminate but the vision of the social project becomes diminished once things enter that realm, you have a war at that point not a social movement.

All that being said, I don't think the protestors are the problem, not even remotely, the inhuman conditions for the average person are the problem. I am also not trying to say a certain way of protesting is necessarily wrong, but this idea that we aren't in a struggle of primarily narrative is a sure fire way to lose catastrophically as the left which to be honest France should be alot more cognizant about given their history than they seem to be...

We all know rightwing fascists need and deserve to be punched in the face, but if you lean into that unreflectively you make it easy for them to portray the situation as a tit for tat fight rather than an existential struggle against dehumanization.