You have more fun when you have grown into the psychological condition of being a child rather than a helpless infant dependent on others for everything. You have the opportunities to go to all sorts of places and explore them without supervision and to find new things you haven’t experienced before. You get to meet new people and play with them and find out what they can do and what you can do together. You get to take things apart to find out how they work and maybe put them back together. It’s fun climbing up on things, and going into special places like dark rooms and being a little scared, but always there’s something fun to play with. You get to have some big toys too that you can ride around on, and have your own computer with some of your own games on it.
Sometimes, after a while, things aren’t interesting anymore so you have opportunities to turn your attention to things that are interesting. If you are lucky you have some people around with access to new stuff and they encourage you to play with it, to make it work, to do interesting things with it. Sometimes, when those people like what you have done they give you presents of even better toys.
If you are unlucky the people in charge of your situation may be mean and complain a lot about everything you do. Even when you do what they say they want you to do they complain and sometimes punish you. That’s a bummer, but usually you can get away and go somewhere else and do things that are more fun, like breaking stuff or beating up on the inferior kids. It is fun to be in control of other people.
Being a child is fun because you are in control of things and people.