Well it's based on a fact, iirc the real thing is domesticated cats learn to keep their kitten mew because humans respond to it, nothing to do with imitating human babies. But that does mean that only cats raised by people meow.
I always believed , though im not a biologist, that they kept doing it because they got something nice as a reward. Pets, food, water, door that is being opened,... The meowing is linked to getting something good so they keep doing it.