For instance, look at Dmitri Glukhovsky and his Metro books - be basically allowed anyone to write any books placed within the same universe, still using the "Metro" logo and characters. Dozens of other books appeared, telling the tales of other metro systems elsewhere in the world and how they've dealt with the apocalypse - but the point is, all those other books have only increased the popularity of the original, and expanded it.
The other good example, weirdly, was always Star Wars books - especially pre-Disney star wars was very lenient with what stories could be told, and unless it was just straight up smut it would be allowed - as a result, star wars fans had hundreds(thousands?) Of books telling stories with their favourite characters and new ones but taking place in the universe they loved. Yes Lucas took a cut, but in general you could just write a book about Han Solo and it would be fine.
That's how copyright should work. Why not let other people tell stories with Pooh and the rest?