Public political protest marches can be a very effective tool to demand and enact social change. Just as the feminists do it, who are the best proof. Feminism is nothing but organized bullying and extortion of privileges by "protests" as a tool. Pussy hat marches, anyone?

So why don't men march for their rights and against the abuses committed against them? I think it is high time to organize protest marches for men's rights. Could organizing start here on this Reddit, I wonder. There is a constitutional right to peaceful assembly and to free speech.

Why don't men, who are clearly the most oppressed and discriminated against group in this society, march?

This type of protest happened before, namely in South Korea. While this article (originally form CNN) is extremely biased and describes the protest as "a small group of angry young men" it gives a good description of what's going on there. The title is misleading, too, they are not fighting against feminism but against discrimination, but it is impossible to find a balanced article about this.

https://www.koamnewsnow.com/south-koreas-young-men-are-fighting-against-feminism/

Side note on pussy hat marches: have you ever seen a man who wanted to wear a penis on his head? I think wearing your naked genitalia on your head is the definition of sick and perverted. But this just a side comment.