these kinds of attacks are not that far out of the norm in muslim culture. they may be condemned by a technical numerical majority of muslims, or at least something close to approaching it, but they're not that unusual. that's why it's easy to understand what it is with little context around it - it happens all of the time in many majority muslim societies and it would and will generate a large minority of support for what it is, which is a muslim man smacking a bitch down for talking back to him and, ultimately, for being immodest. he acts that way because that's what he was taught to do by the men in his culture.
there's nothing left-wing about this and it has little to do with the school system in france. this is political violence by an increasingly organized far right youth movement of religious extremists that are angry about muslims losing wars in the middle east and are taking it out on the french society they live in.