Way. Too. Many. To. Mention.
Furthermore, it extends beyond just animated material. It also includes live-action movies (theatrical, and made-for-tv), and TV shows (terrestrial and cable).
IMO, it's a really big problem. Don't get me wrong, realism isn't a bad thing, but at the same time it can actually hurt a project rather than help it. If you focus too much on realism, it becomes so grounded in reality that it lacks the ability to be flexible in its writing, and can actually detract from the project itself.
Case in point: the DCAU. Obviously B:TAS was different and groundbreaking from previous portrayals. A Superman series was inevitable, as was a Justice League series. However, I'd have to say that S:TAS started showing signs of it (especially the two part finale "Legacy"), but it came to a head near the end of Justice League; specifically the series finale. Without spoiling anything, let me just say that Justice League Unlimited was the moment that the DCAU "jumped the shark", because at this point it focused less on writing, and more on showing off how "realistic" the franchise's writing was. For me, it was like "we get it already". For me, the final nail in the coffin was the Batman Beyond "connection", which IMO shouldn't have existed in the first place (again w/o spoiling anything, originally, the timeline of BB was just a possibility, but JLU "officially" made it "canon"); it felt like it was totally made up on the spot just for the sake of making BB "officially" canon. However, a new season premiered after that. This made me wonder if it was possible for a franchise to jump the shark twice.
In the end, depending on the individual project, there's really nothing realistic about realism, it's just the same generic writing over and over again. Instead of being unique, and actually evolving, it's just the same old things that have been done a million times. At this point it goes into the issue of hypocrisy in the industry, but that's another story.
I'm sorry for the long post, but there was a lot I had to say about this and even more still, but for now I'll just leave it at that.