See, I'm wary of statements like these that allude to the "dumbing down" of the viewing public, because they seem to imply that the viewing public actually knows the difference (or at least, can tell when things are different) and actively shuns products that make use of more complex techniques.
Like, just because you prefer media that doesn't challenge you, doesn't mean you will never watch something that CAN challenge you. It simply means that, if you do, you will appreciate it for its more surface-level qualities.
For example, Romeo and Juliet is one of the most famous plays in the world. It contains a lot of deep metaphors and interesting dialogue and character dynamics that maybe most people aren't aware of, but just because the only theme they can recognize in it is "forbidden love" doesn't mean they will avoid the play. It can cater to the tastes of both those who choose to look deeply and those who do not.
Basically what I'm saying is, if simple, "dumbed-down" techniques are proliferating through out the media landscape, it's probably more the fault of the media producers who choose to use them than the consumers who probably aren't even aware of those choices.
I, for one, have never really thought about the camera work in prime-time TV and I don't even know what the 180 rule is. '_' If a show I liked adhered or didn't adhere to it, it probably wouldn't bother me that much.
And although more down-to-earth concepts like how the characters look and speak and whether or not they rehash the plot 5 times every episode (that actually DOES get on my nerves) would be more likely to affect my viewing experience...if there's something that draws me in to the show regardless (the plot, the humor, even the sfx) I'm not gonna drop it on principle alone.
I really think it's the responsibility of content creators, if they care, to weave interesting and challenging techniques into their work, rather than to call out the audience for liking the work of those that don't care. People will like what they like, the best thing you can do is try to improve the quality of the things they have to choose from.