I have a friend / ex who is a mild tumblr feminist, and she utterly despises this term. I don't recall it ever coming up in conversation, but she posts about it on fb every second Sunday.
I can see both sides of the argument.
Yes, the term is male-centric, you will rarely see girls using it, but isn't it obvious why? Because the way sex works, guys have to do 95% of the 'chasing'. Hundreds of thousands of years of that behaviour, and our brains are probably going to be wired to seeing members of the opposite sex as a prospect much more readily. Is it really a surprise then that guys find themselves, exponentially more often, in situations where they were seeking more than a friendship, and the girl wasn't? And that a term arose for such situations?
Yes, I've seen cases where it's used with bitterness (more than seems warranted by being turned down), that when some guys use it, it carries a sense of 'I put in all this effort, I was owed something", that some guys lean on it when the reality is, they should've said or done something earlier.
And I've also seen times where, in the scenario the use of the term is describing, the girl's behaviour was itself appalling - girls who have exploited friendships with guys because they knew they had feelings for them.
I had a friend some years ago. I had feelings for her, told her I liked her, she wasn't interested, but we decided to stay friends (many of my close friends are girls, not one of those guys who can't do that). In the holiday period which followed, for which I came to find I had no prospects but to sit at home alone or travel alone, she suggested, and eventually insisted, I travel with her to another country, to which, considering I was trying to get over feelings for her, I at first said fuck no, but with time and pressure, reluctantly agreed. A few days into the holiday, she confesses she hasn't saved for it, and asks me for money. It was years before I actually processed it properly, but I really think that was the main, if not the sole reason I was invited on said holiday, and why she practically begged me to come. She had realised after booking that she was short on money, and in light of recent events, I was the perfect friend, with that perfect cocktail of rebutted, reluctant, but still present feelings, and by exploiting those feelings, said holiday could still go ahead without any sacrifice having to be made on her part.
I don't consider what happened there an example of the "friend zone", I had been told no, and was going forward with the friendship under the impression that nothing would happen, and I had to swallow my feelings and deal with it. But considering the fact that she recognised those feelings of mine and intentionally manipulated me and our friendship with them, I think I can understand some of the bitterness some guys are slinging when they talk of situations they describe as the "friend zone".