I found that just a quick note about "leftist" / "socialist" in the bio helped find comrades, idk if the people I've seen were as militant as I am but there are plenty of socialism-sympathetic cuties out there. I do find that I'm pretty much the most radical person I know on those apps. Depends on how strict you are in your taste, like, is a demsoc is too far gone for you? Cuz I was one of those once, until I got radicalized. I think the important thing is finding someone who is empathetic to your worldview, and showing the same to them, while being clear and genuine about what that view is and why you hold it so strongly. With the right person, that kind of philosophy and dedication can be really attractive.