Taking care of a kid is not exactly grueling work for 18 years, it’s a lot easier after the first 3-4, and is also very fulfilling even when it’s tough. Assuming you have normal human caregiving feelings and so on.
I don’t know why the internet is so anti-kids, it’s pretty baffling.
Obviously babies are demanding, especially in countries with shitty parenting support and daycare, no parental leave, and a work environment which is hostile to normal family life. But kids are fine, funny, and a joy to be around, most of the time, at least. It’s a bit like work, many people bitch about it but they still find it fulfilling.
Also, I know people my age with no kids and they a constantly complain that they’re tired 😂 probably they’re just getting old.