It is likely that much of low modern fertility is lesbian bed death for straights. Without a sufficiently masculine presence, the woman doesn't feel like she's married and thus is repulsed by the idea of having children, rather than desperate for more children, as is normal.
Refresher: the planet Mars is overmasculine and the planet Venus is overfeminine. Mars reached and pushed so much everyone died and its atmosphere escaped. Venus clutches so hard it smothers everything.
The primary driver of lesbian bed death is the fact women, by default, don't initiate sex. A relationship based on the woman habitually overcoming her own femininity only works in the long term if there are no women involved. Modern Fascism is feminizing. Everyone clutches to themselves so much that they cannot connect with another. Everyone retreats into their shell, clenching the brace so hard it melts lead. Even the men don't initiate sex, both literally and figuratively.
Some children are still born only due to extreme desperation on the part of women, and the fact men aren't exceptionally good at being Fascist. They accidentally, unintentionally act masculine. Women who are around when these men make these oopsies end up having children.
In general, feminization drives atomization. Everyone is waiting for prince charming to sweep them off their feet. To (gently) invade their overly-closed-off spaces. To force them to be intimate, the way a new baby somewhat violently forces its way into your life. Women are not designed for voluntary connection. (This is bad, but it is what it is.)
It is likely that women invade male-only spaces as an
expression of babby's first empathy. Women who want to invade have a
deep unmet need to be invaded. They want men to crash the knitting circle and make asses of
themselves, so to speak. Yes crash, no don't actually knit anything. It's fine to "contribute" a couple six-packs, one of which you drink yourself. Or indeed anything you happen to feel like doing.
Of course these days that sort of thing
is actually illegal. Harassment &c. Men allowed male-female
relationships to be literally outlawed, to everyone's sorrow. Naturally the rectified punchline to the Aristocrats joke is "Democrats!"
P.S. Alternatively you can stop suppressing your masculinity and watch women react like you're wearing a catnip suit. The contrast with your poncy competitors is nearly irresistible, even for men who ought to be average.
Remember that for a man, masculinity feels boring. Supply and demand: unless you're unhealthy, you have an unlimited supply of masculinity and thus the price for you is approximately 0. You don't have to do anything exciting (for you) to be exciting to women. Just be obviously yourself where she can see it. Her tits don't need makeup to be exciting to you; for a healthy woman, they're fine the way they are, she just has to not-hide them. Remember, the converse is also true.
I guess I should mention the shit test. Women will often act like they're repulsed by masculinity, to test whether you're doing it only because nobody has told you to stop yet. Unlike a man they can't see at a glance - or indeed after a good long look, for that matter. Womens' person-judging skills are usually horrible-to-nonexistent. Also precisely because they're so attracted to it that to retain any semblance of self-control they have to violently pretend to themselves that they're not attracted to it.
Rather similar to the way men react to 17-year-olds in America, come to think. (Not as different as you thought, eh?)