Yeah, no. I'm positive it's more along the lines of, "Yeah, we know nothing is going on onscreen but the audio that's accompanying it should make up for it."
See, as far as I'm concerned The Simpsons has been garbage for a decade now and people are still watching it. The merchandise sells like hotcakes and the show is in no danger of going anyway. In fact, The Simpsons is actually proof positive that an established franchise can turn into complete junk and it will do nothing to turn viewers away. Yes, the ratings have gone down a bit in recent years, but IMHO I think it's due to more factors than just the show's quality.
And since FG has actually gotten much better since the somewhat iffy season 7 your point is kind of moot anyway.