why most people still want to have kids ?

I think it's safe to say that having kids is a basic biological function. If it weren't the case we wouldn't all be here today. It's a basic survival requirement of nature.

The hormones rise and we can't stop ourselves - just like the rest of nature.

I've been watching the Mason Bees in my garden. The females are laid in the nest tube first, followed by the males. The result is that next year the males will exit first and wait to pounce on the females as they exit next! The males then die! And as far as I could see, the males don't even bother to feed - their life is so short. The females then spend their slightly longer but still short life laying eggs and provisioning new nests.

We're no different. That's what life is all about, struggling to bring up kids to keep the species going. We've only a slightly longer life than the Mason Bees above because it takes a bit longer to raise our offspring.

Sorry to bring such gloomy news!