After watching ur link....well im cant believe what im gonna say but even though Argentina is much more alt leftist shithole than Brasil , it is far less violent in most marches.
Last year they started going batshit crazy , like buncha feminist broke a lot of public and private property.
idk how much farer left is this country going , but i do know it is definitely going further on the left.
I really hope Bolsonaro puts some order now in Brasil , marches like that one you linked should be illegal , they can't block free roaming of individuals, at least not in our constitution , it shouldnt be different in Brasil.
And certainly they can't give fucking temporal immunity in marches to those alt left scumbags.