I get that for men it can also be difficult or awkward and can make them insecure.

Big difference is though that when having sex women's bodies produce oxytocin which makes them want to bond, have a commitment, and all that comes with it.
This ALSO happens when a woman has NSA sex. It's our biology, not something we can control.

Men on the other hand release testosterone which makes them want to be off after the deed to impregnate other women.
MEN DO NOT BOND THROUGH SEX, WOMEN DO.

That is why NSA is much harder for women and usually only happens when alcohol came into the picture.

As such, what I wrote is far more applicable to women, certainly in the early stages of a new connection.
This is also why it is advised to women to not have sex with a man very early on. Sex CAN work as bonding, add to bonding, for a man but there have to have been other emotionally bonding moments for that to happen. Without those moments a man can have sex and simply walk away, never show up, never call again. Likely even forgot the woman he had sex with exists.
It does NOT work that way for a woman.

Based on all that, I think the moments that a man can feel insecure about having sex with a woman is AFTER there have been emotional bonding moments. So when having sex means something to him other than getting his rocks off.
GEnerally speaking there's loads of men out there that only seek that: getting their rocks off, so as a woman you have to be careful, and sift and sort or get hurt. Or pregnant even as generally speaking a man doesn't have a condom with him or he doesn't want to wear it.