It should be the case. In practice, it is often not the case. If you doubt this, search 'feminist' on youtube, watch a dozen random videos, and try to identify the issues and beliefs which the speaker sees as intrinsically 'feminist' ones, and ask yourself whether those issues and beliefs are really in support of equality. Its a bit of a mixed bag.
I'm not trying to attack feminism, as I strongly believe in equality and we have a lot of work to do. And obviously there are anti-feminists who have always tried to distort the messages of feminists, and fabricate their own. But these days, those manipulators don't have to try very hard.
I don't see how we can fix this, though. The commercial approach to a similar problem would be absurd in this case: creating centralized certification body regulating which 'feminist goals/speakers/blogs/books/lines-of-argument/etc' are deemed 'truly feminist'.
Is this not the case?
In the real world, it can be used as a fig leaf to justify a variety of abusive behaviors. For some people, that encompasses the whole of their experiences.
We disagree that this actually changes the meaning of Feminism.
Yes, some horrid people need an excuse to dish out abuse and Feminism often becomes that excuse (I'm thinking about everyone who's ever used the potential-rapist argument).
Does this taint Feminists, the group? Maybe a little, yes.
Does this taint Feminism, the idea that genders should be as equal as possible? Well, IMHO, no.
Feminism was about seeking equal rights and equal opportunities for women. In the West it largely achieved that goal (we're not there yet, but consider where we started). Thanks to tumblr, twitter and the blogosphere echo-chamber, the feminism most people become aware of online is very different from that.
Worse yet, there is no such thing as "the feminist movement" (anymore) by a long shot. It's become a broad term that encompasses everything from egalitarians to misandrists. And any criticism of the later group is always portrayed as a criticism of the former (which is why we end up with this entirely pointless MRA/SJW shitstorm-on-demand situation we have now).
Nobody is forcing egalitarians to call themselves feminists. But clinging to that label and pretending it hasn't changed its meaning is no different from trying to distance your communism from Stalin or your nationalist socialism from the Nazi party.
I prefer that definition, yes. But the important part of my sentence was "locked in". I was referring to people who are incapable of acknowledge that the word feminism is abused, not just by anti-feminists, but also by some self-proclaimed feminists.
If someone really thinks that feminism can only mean 'equal rights', period, end of conversation, talk to the hand - then conversations with people pointing out problems in the feminism movement will suffer from equivocation fallacies.
Too many people who call themselves feminists actually do not believe in equal rights, and present feminism as a justification for bad behaviors.
If this is how you experience feminism, this is going to influence your notion of what the word feminism actually means, in practice.