Oh, I have no issue with connecting him to a vigilante. I do have an issue with people thinking that is somehow a universal negative - that simply calling Rittenhouse a vigilante is a negative statement about Rittenhouse's character when, in fact, it is quite the opposite. It is a hell of a positive statement about him considering he is willing to stand up for what he believes in even to the point of placing himself in danger.
In this particular instance, the negatives are on the rioters and the fact that the government openly abstained from doing not just it's duty but its moral obligations to the people that it is supposed to serve. The same government that is trying to sacrifice him in the name of saving face.