A while back I mentioned the dangers limiting the freedom of today's kids. Unfortunately protecting children from danger can also stifle their imaginations.
Back when kids could go out and play with other children without adult supervision they often pretended to be various sorts of characters and acted out stories until they were well into their grammar school years. It wasn't unusual for fifth graders to join with other kids of all ages and interact as pirates, princesses, cowboys, dragons, or space explorers.
However now children are constantly with others about the same age and under adult supervision. With grownups always watching, most kids stop acting out stories they make up and pretending to be fictional characters by first grade. Instead they play organized games when they're outside together.
Modern devices like cellphone apps do allow them access to imaginary worlds, but the games and interactive videos allow only limited possibilities. At least if they discover the joys of reading and immerse themselves in fiction books they can still use their imaginations.