My wife and I teamed up and had 5 children between 1966 and 1978 (She did the hard part) We never knew the sex until the the little sweety was born.
Now days, we know if we're having another grandson or grandaughter months before they're born.
Big difference.
Names = Male or Female? Better have one or the other ready for the birth cert. info.
clothes are not that critical. But would you want to leave the hospital with your baby boy wearing a frilly bonnet ?
paint the nursery pink or blue ?
But the big advantage of knowing the sex before hand is that it gives the parents a critical bit of information to start the bonding.
"Oh, look, Jim, Polly is kicking me like a little mule!" etc.
PS I wanted a boy very strongly. We had - girl - girl - boy - boy - girl. The suspense was intense. Wouldn't change it for anything