In my experience, this has been an easily observable constant in every discussion I have had about this. Women when hearing the term "friendzone" and its general description see it as a self-imposed issue that is to be solved by the guy either giving up on ever advancing into a romantic relationship or working up the courage to make his feelings known. Now, there are many instances where this is indeed the case, but I would argue that most of men's biggest complaints regarding the friendzone refer to a much more insidious situation, wherein the girl is clearly aware of her "friend's" feelings for her, but leverages them for her own benefit while feeding slivers of attention, validation, and maybe the odd bit of leading on to keep the guy (who in this case is assumed to be somewhat naive or otherwise easily manipulated) around because of the utility he provides.

I think one example that really boils down the frustration and animosity so many young men feel in scenarios like this is highlighted in this post: https://www.theonion.com/but-if-we-started-dating-it-would-ruin-our-friendship-w-1819584582 (yeah, I know its an onion article, but I'm sure most guys who read this can understand what's being conveyed and how uncomedic it is to be the man in this situation).

Oddly, this misunderstanding seems to be much less prevalent in society at large when women complain about being "fuckzoned", where they are used solely for sex by a man they admire and would like to have a deeper relationship, as most men seem to have an understanding of how this could lead to a lot of hurt and anger.

I feel like if women made the effort to shift their view of the term from what they immediately understand and consider the other side of this, there would be much less vitriol and anger on both sides whenever the "friendzone" is brought up.