I will say one thing though, it is still better than Family Guy. I'd much rather tolerate The Simpsons at it's current, bland self than the terrible humor Seth MacFarlane puts out.

The fact that we're all talking about how The Simpsons have run it's course raises an interesting point about the show now and days: who is watching the show at this point? How do they have any viewers at all?

Really, what I think keeps The Simpsons on the air is just the fact that it's really profitable as a franchise. It may not generate the ratings from back in the day, but what keeps it afloat is the merchandise, which sells a lot. A lot of the Simpsons fans that likely buys the merchandise though, would more than likely be a fan of the classic Simpsons episodes, and not so much the new ones. There was also the fact that FXX aired the Every Simpsons Ever marathon a few years ago, which really brought a lot of attention to the series. I'm sure that brought in a lot of ratings and viewers for FOX, as a lot of these episodes that aired, people may not have seen them air on TV in years, as before that, most TV markets that would air The Simpsons in syndication would air only the last few seasons at the time. With those revenue streams combined, FOX is able to get away with poor ratings of The Simpsons and keep renewing it, so long as it continues to be profitable through other means.

Here's another take, one that I largely agree with. https://www.theguardian.com/commentisfree/2018/nov/01/apu-simpsons-hero

It's true that Apu is something of a stereotype, and in this age maybe shouldn't be voiced by a white guy. But he's been a character with depth, his heritage has been a serious topic, and he has as realistic a life as any other character on the show.