One thing I’m suddenly thinking about is Black Widow’s reputation as a femme fatale and where it comes from. Because both in the MCU and in most of the comics I’ve read, there’s not a whole lot of her seducing men/using sex to get what she needs.
In comics, her very earliest appearance with Iron Man in Tales of Suspense #52 has her serve as a distraction in the form of a pretty face, but there’s scarcely anything there, and while there were some hints of it in Richard K. Morgan’s Black Widow run overall I find it’s much more typical that the men around Natasha assume she’s there to seduce them, when in fact she has other means of getting what she wants.
(Of course, the above panel is having it both ways. Natasha’s reason for not sleeping with her mark here is that she’s “involved” - and the suggestion of sex is there, along with a close up on Natasha’s thigh.)
Outside of Ultimates (and I don’t talk about Ultimates) sleeping with people - or even trading on her sexuality that much - just doesn’t seem to be a thing Natasha really does.
And then in the MCU - in The Avengers she trades much more on her perceived vulnerability and assumed weakness (as a woman) than any kind of sexual appeal (“just another pretty face” and the whole scene with Loki). In Cap 2 there’s even less - the closest thing I can come up with is the “hello, boys” in the scene on the Lemurian Star and that is immediately followed by a brutal fight rather than a seduction. Later on, with Sitwell, her interrogation style is to kick him off a building.
What I’m getting to, I guess, is that it seems to me one of those things that kind of comes out of nowhere. It’s an assumption - like the man in the panels above, that because Natasha is a woman and a spy and wears a tight black suit, that her modus operandi is sex. And if it’s an assumption made in universe (by Natasha’s interrogators and opponents) then it’s one that, despite its being proven wrong, is perpetuated out of universe in discussion. (Think of the reviews of both Winter Soldier and The Avengers that dismissed Natasha as sexy eye candy in fetish gear.)
It’s just - funny, for lack of a better word, that no matter what canon evidence there is, Natasha is still overwhelmingly perceived as a femme fatale figure trading on her sexual appeal, when it’s been demonstrated in both comics and the MCU that that’s not what she does. It’s like the trope of spy woman = sex object is so deeply embedded that even with two movies and several volumes of comics to the contrary, perception still sticks Black Widow in that box, again and again.