It was about how having kids "traps you in the system". You need to work and so on so you can take care of your kids. Sure you can just abandon them, but most people don't want to make their kids suffer and feel obligation to raise them either morally or legally. Therefore they are stuck doing a job and having a life they wouldn't necessarily want if they hadn't had kids. They're not literally "trapped" like someone isn't literally stuck in prison, they can escape if they are creative or lucky enough.