Unfortunately, those are largely landfilled. That is the big problem.
There are lots of groups now looking at the idea of sharing so that not everybody has to buy. Every time you have a kid, you have to buy your own fleet of toys or clothing, and clothing is another big source of plastic pollution. It's the idea of sharing so that your child for this stage of development likes these toys and needs this clothing. You're going to use them and make sure these products are durable and can be washed, sanitized and passed on to somebody else.
We need systems for that kind of reuse and repair, and we don't have those today. There are some Facebook groups making that happen or other types of community bulletin boards through which some of the sharing happens. A toy library, for example, would be a fantastic thing for a community. People could share toys just as we share tools sometimes today or share books.