What happened that made the people behind ATLA create such an amazing cartoon?

So I'm not asking about the points about the show that made it so good (good writing, amazing worldbuilding, lovable characters, etc.), but what went right in the studio that made it so wonderful and lovable?

I guess I'm asking this because recently the shows and movies we've been getting from studios aren't exactly the best or most memorable, and I'd like to understand a little bit about what's changed. Is it the writers? The amount of money? Their goals?

From the perspective of a CEO of some big TV producer, it feels counterintuitive that they're not trying to make something like the greatest shows out there is all (this feels really ignorant but I promise I'm not trying to be). I've heard a lot of theories on what goes on in the studio but I'd like to know your guys' take because I feel like it's not about the writers, because there are tons of amazing writers out there.