But in opposition to the those, (anarchx) nihilism can be the way for people to go from a passive to an active role in society. Instead of seeing the end of the world (as we know it) as a reason to resign, it motivates to manage atleast a fuck you to the world, however small or big.

That's not the same as contributing to a more just human future. The mindset explicitly embraces the idea that there is no worse state possible than the current state of affairs - which the lives of some several billion people might disagree with. "Pure negation" necessarily implies negation of all institutions of current society - and combined with the idea that "There are no demands to be made... no political programs to be followed" it's not much more than a parody of nihilism taken seriously.

On top of that, if it was sincere, it would be immediately and violently insurrectionist; if it's insincere, then it's just an excuse for any antisocial behavior without regard for consequences.

And yes, that might sound like angry teenager stuff. But me, not so much a teen, can atleast resonate with that way more than with other contemporary outlooks on the world.

When I suggest throwing molotovs might not be a bad idea, I do so with the presumption that the people throwing molotovs have demands, a vision, or a political program. The idea that "Society bad, therefore, any attack on society GOOD!" is not only Manichean idiocy, but intuitively repulsive when any of the actual consequences of purposeless and targetless attacks are actually considered.