I mean, I can go one deeper than that. I designed, built and own a half-million dollar medical facility where the clients question my presence every time I'm there.
Fundamentally, pregnancy is about motherhood. It has fuckall to do with fatherhood. And when our communities were closer, and when our social net was stronger, motherhood was all about the women of the village/tribe/bowling league getting together and celebrating the bond of women necessary in bringing a child to term and then raising it in the community. Midwives were generally the unmarried medical practitioners who held a repository of how to make a birth go right; with no medical expertise, the fatality rate from childbirth was about 1 in 5 (women's pelvises are a compromise between being able to walk upright and being able to birth viable offspring that require human fetuses to become human children about a month early from a zoological standpoint).
Then we modernized and took it out of the hands of the village and into the hands of medical professionals. Morbidity rates plummeted and mothers and babies survived with such regularity that childbirth became mundane, rather than risky. This kicked the womenfolk out of the equation, however, so they had to create new rituals around it, like baby showers.
Then we eroded the social fabric still further such that your friends in high school aren't your friends in college aren't your friends at work. You live a thousand miles away from your relatives. And now, the tight-knit camaraderie of motherhood is replaced by that poor hapless, feckless, no-handle-on-this-shit victim of circumstance, the husband.
And since he has zero traditional role in pregnancy and childbirth, the rituals industry has had to punt.
With medical ultrasound becoming common, and the mystery of a child's gender being solved long before birth, the rituals industry saw an opportunity to cash in once more on a shattered tradition and thus, fuckin' gender reveal parties. Another terrible attempt to replace kinship with themed paper plates and Costco cakes, except since it isn't a baby shower, there's a higher likelihood that the man is going to get saddled with "choosing" what the fuck it's going to look like. Never mind the fact that historically, men just grew their beards out or some shit. Imagine Falstaff going to a fucking "gender reveal party."
Fundamentally? Every stupid awkward social ritual we have around birth is an ersatz substitution for a natural social and familial connection we've severed over the past 150 years. But sweet holy jesus. They're all some form of "I don't have enough close girlfriends therefore we're roping your friends into this bullshit because Facebook is fundamentally dissatisfying."