Yeah, no. A female character dying is not "fridging" the character. Fridging means that you are providing a male protagonist a motivation that is entirely based on the needless killing off of a love interest character.
1) While they are not romantically involved, there is a love between them, or her sacrifice would not have worked. 2) Hawkeye wanted to die. His stint as Ronin is him basically going out to kill people until one of them finally gets him. Her death makes it so he *has* to keep going on, or her death is in vain.
Sounds like giving a male character a motivation to me.
Note, also - two out of two people sacrificed to get the stone are women. And they do it so men can get the stone, and go do big things with them. The sacrifice is very much used as 'kill a female character so the male character is enabled to do what they do'. So, I think the fridging point has merit.
Black Widow dying was neither needless (as someone had to die, be it BW or Hawkeye)
Setting up the plot specifically with "someone dies here" and only using it on women who have a love-relationship with a male character, and claiming it isn't fridging is kind of like saying something really snarky, but claiming it is okay because you put a smilie face on it.
The movies are still good, but this isn't their finest moment.
While I can see that a particular interpretation of Black Widow's death might be problematic, this particular issue isn't one of the problems.
And, as far as "she's a monster because she can't have kids" that's also missing the point. The audience is supposed to look at that and have the same reaction that every other character has - she's wrong. She's not a monster.
With respect, you are missing part of the point of the pushback on this.
The issue isn't about her feeling she's a monster, and being wrong about that. I mean, yeah, she's not shown to be a person with flawed judgement, so suddenly she's wrong about this one thing? But, okay, we can swallow that.
The issue is that it is positioned and presented such that, for however many people she has killed, that isn't what makes her a monster. In her eyes, not being able to have babies is what makes her a monster. Now, that's a thought you could spend some time with, and maybe work it around and have *her* come to he conclusion that's she's wrong, and that's fine. But, they don't have time to do that. They just dump it out there, and leave her with it.
I know a woman who is barren. Can't have kids. It is kind of a sore spot for her. She left the theater in tears when those lines came out in Ultron. Another woman I know had her tubes tied, for personal reasons. That scene, suggesting that a powerful woman - her representation in that movie - feels that what makes her a real person is her womb, made her angry.
*DO NOT* tell me how these women were "supposed to" feel there. They felt as they felt - and those feelings were valid. The film makers didn't think enough about how those words could come across to the audience. Having made that error, they should have learned from it, but apparently didn't.