I think one problem is what wedrifid says: it is difficult to work out what your comment actually means.

• "the empirical claims of feminism are now successful": what does it mean for an empirical claim to be successful? Is that the same as "true", or something else?
• "but they did exist": why "but"? what's the opposition between existing and "being successful"?

I gather that you were disagreeing with Argency's statement that feminism "doesn't (or shouldn't) make any predictions about the way the world actually is or will be" on the grounds that you consider that feminism does (among other things) make claims about how the world is. Fair enough (and for what it's worth I'd agree), but it seems to me that the obvious diagnosis is that you and Argency disagree about what "feminism" means, in which case merely saying "but it does make empirical claims" doesn't achieve much.

So: two problems. A statement whose meaning is hard to make sense of, treating a disagreement as one about how the world is when it's probably actually more about how to use one particular word. I'd guess that whoever downvoted you had one or both of those in mind.

(I'd also say: being downvoted by one person is not particularly strong evidence of anything; don't get upset about it. But if you find yourself being downvoted a lot, the chances are that either you should change something or else LW just isn't a good place for you.)