I mean, you're being sarcastic but so many boomers seem to genuinely believe that and cannot understand why it's considered "wrong".

They don't think. I'm not being a dick. Seriously. If you ask them why they hold a certain belief they will tell you one reason, maybe two, but no more. They can't tell you any more reasons because they never thought past the first one. By comparison i could probably list 6 or 7 reasons why I'm not having children, because it's something I've thought about a lot over the years.