What works for me is to look at analogous situations.
So there is this show title "To Catch a Predator". The show catches at best a small fraction of potential online predators out there. Now I thought the show did a great public service catching the few hundred they caught, but again black and white thinking is easy to fall into. The black or white (or A or B) solution to the problem is to try and stop the problem by arresting the predators (choice A), or by trying to stop the minors (choice B), but ignores other choices like both. Since the predators are out there and clearly are not going to stop (many of those caught had seen the show and knew it might be a setup), as a parent I'm in favor of both. Do more to catch the predators while at the same time I took responsibility for my kids and made them aware of the dangers, and to avoid putting themselves in positions that could put them at risk.
In non black and white thinking multiple things that are in conflict can be true at the same time. So for example, you have a right to do X, but at the same time, doing so may be dangerous. For example, I have the legal right to buy a steak dinner and eat it in front of homeless people in a dark alley, and if they attacked me and took my food they'd be legally in the wrong, but still most people would have said to me, xdude, you're being incredibly naive about the real world and human nature.
So I think there is a blurry line between whether people react negatively to a march like that because they are denying rights, or because they are frustrated with naive/wishful thinking that thinks that the dark side of human nature will disappear over something as simple as marching. And for some people it's both. They both agree woman should be able to dress how they wish whevever while at the same time are frustrated by naive/wishful thinking that predators will stop being predators due to marching.