I'm sure this has already been written but here goes:
The TV audience today is not the same as it was in the 70s, 80s or even 90s. The audience today needs something that is intelligent, not full of politically correct cliches etc etc.
I think if DS9 had been made today(Or Babylon 5) it had been a bigger success than it was because today the audience demands story arcs and plausible plots that aren't rediculous.
Nah, they just want to be entertained. Sometimes its just a singing competition. Other times it might be what amounts to a Soap Opera with zombies. No one cares if the shows contain "politically correct cliches" or if the plots are "plausible". Sometimes the more ridiculous, the better.