There is an excellent documentary series on Netflix called The Toys That Made Us which covers a lot of these. The Star Wars episode was very interesting, it gives you a look at the wheeler-dealer moneymaking side of the franchise (and some of the early toys are hilariously bad).

Some of it is kind of cool, and produced some genuinely enjoyable cultural icons... but also a lot of it was very manipulative, and you end up realizing how much of this cultural period was manufactured, packaged and sold to us through TV.