So oftentimes you hear from feminists and others this thing about how words aren't defined by the dictionary<sup>1</sup>, but how people think about and use them.

So why are they having such a big problem with most equating feminism with a hate ideology of men and boys? That's how most people experience it after all.

If you experience feminism as a hate ideology of men and boys then make it clear! There's no abstract or ideal idea of feminism. It is what you experience it as and you should say so. Feminists themselves have no qualms with subscribing to this way of thinking. The very same way they erase, by definition, sexism towards men we should erase feminism itself.

[1]: a slew of words for various bigotry taken to refer to prejudice in relation to some characteristic by someone coming from a position of power rather than just prejudice in relation to some characteristic by someone(see sexism and racism).