Eh, I think the reason is more fundamental. Furries are a niche group of people, mainstream content is about $$$, and you don't get the big bucks from the small cliques. Before a show can be made specifically for furries it has to be proven that it would be very profitable to do so, but as it turns out, you can create a show that both appeals to the general audience and furries. Examples: Zootopia, Disney, etc. But it would be unfair to say any of these were created with furries in mind, I'm not exactly sure why animators tend to favour animals rather than humans, but I think it has to do with them being easier or more interesting to draw. Either way, it's more fair to say that furries were created from those movies like Zootopia, than those movies created for furries.
I guess my point is, furries don't really have an impact on anything, and often fit into the target audience of other things, so there's no real need (on an economic sense) to market something specifically for furries. Bronies got some shout outs in MLP because they were not the target audience but ended up being a large following, some shows/creators of mainstream media have commented on fursuits of characters, or furries who drew their characters, but again that's just because they're part of the audience in a way.
So the question you have to ask yourself is, if I was a TV executive interested only in money, why would I market something specifically for furries? Can I expand it to the "Kids" genre which is considerably more profitable?
Indie developers do it for the passion, big producers generally do it for the money.