I see this more expansive story and lore as an evolution of the appreciation for a property. Take comic super heroes. Yes comics have always had a (tenuous) story line, but the way they work has evolved. Back in the golden age, there was no qualm about a dude putting on glasses and being able to hide is alter ego. Things weren't looked into all that deeply. People just accepted it because.. powers!
But then the kids that grew up loving the stories wanted more. HOW is it Superman can fly? What's the physics behind it? Why didn't people immediately recognize that it was just Clark with no glasses on? Sure, Bruce Wayne dresses as a bat and has cool trinkets, but how does he come up with them? Oh, well Wayne Enterprises is basically Batman R&D Limited. What happens with all the collateral damage that battles cause? Super Hero Registration Act, or - for the plebs - the "Sokovia Accords."
Stories got darker, more serious, and more cohesive. Same with Transformers. Would I go back and change G1 for what it was? Shit no. Those 21 minute commercials for toys (that totally fucking worked) are awesome for what they were. But then the fandom got a little more mature, wanted more detail. Background on Cybertron. Who were the Primes. What happened after the movie (because season 3 doesnt count). Who the fuck was Unicron, and who made him. So the next evolution, Beast Wars was intended as -yes, a show for children- but it wasn't necessarily a creature of the week type show, it had a storyline because it made people come back. The show was no longer really a commercial, it was a story.
TV is no longer the same. In the 80s, a show about a dude that flies a stolen battle-copter saving the day out of the goodness of his heart from week to week, even though he was looking for his brother the whole time - worked. . St. John took a back seat to the episodic...ness. Didnt really need a long drawn out story.
But now, you've got seasonal arcs. Forshadowing. Big bads that start out as little goods. Arcs that span the entire show. Spinoffs. Cinematic and Television shared universes.
The stories just grew. It doesn't invalidate the originals. Just like the admittedly badass Battlestar Galactica 2003 was fucking tiiiiiiits. Eddie Olmos? Tio Eddie? Shit - I'm in. But it didn't make the OG BSG shitty all of a sudden. It was just... more.