This doesn't even apply to arguably good shows like The Killing, whose later Netflix-produced season is so awful it's embarrassing, not because it appealed to a wider demographic -- it was pretty niche -- but simply because it was terrible, badly acted and worse plotted. I've no explanation in this case.
I'm surprised by what people are saying about Bright. I disliked it because it was a bland knockoff of Shadowrun and similar scifi-with-orks-and-elves settings, with weak SFX and an even weaker plot. The commentary about racism -- whether well or badly done -- didn't even factor in my dislike. Bright is indeed a by-the-numbers urban fantasy made to appeal to a wide demographic, with nothing interesting to say about scifi, fantasy or even action. It was quite accurately described by the press as "a movie done with an algorithm". So of course it will likely have a sequel!
I really hope bland shows aren't the future of Netflix, but I fear they will be because they make business sense.