Many couples we know our age (early-mid twenties) don't have kinds unless they had them by accident. It's all about waiting until the new system. We had decided that, looks like that will change haha.
Many also worry they couldn't afford it, most young JW couples I know are terrible with money. The feel is a lot different these days that even 10 years ago, a lot more couples don't have plans for kids, just plans to go down to one income and pioneer or things like that.
Just my observation