Well, i agree to you on some points: It is very possible to overextend even on the very good franchises and Batman had "enough attention" through the last few years. DC (i'll just use it right now because it's Batmans "origin" and shorter than writing Warner Bros. all the time) should take the chance and make some other good movies without relying entirely on Batman, obviously, it would not only extend their ground, but the fundaments they could build on.
However, i think you're a bit unfair with this, in a way. You don't want some Justice League movie to suck, i wouldn't want that either and while you mentioned Marvel's Avangers as a comparison, which is necessary at this point considering the movie more or less dominated last year, but on the other hand, isn't Marvel just as flawed in this way as DC is? When i look at the Avangers i think one of them stands out very similar to Batman and who could that be? Iron Man, who else?! He is pretty much Marvel's version of Batman, some stinking rich guy with enough intelligence and self-claimed "justice" to go off and fight tons of bad guys as a hobby. Don't get me wrong, i've liked both at very equal levels and much more than many others, probably because of their similarities, qualities and flaws compared to other super-heroes. And this year another Ironman movie comes out, it will very likely shovel in another bunch of money for Marvel and he had several tv-franchises and games as well, recently even added an "anime" to that list (yeah, not going to talk about that one further).
In fact, both, Marvel and DC had respective works of success and fuc*** up some others. For that i'd like to remind you of the Green Lantern movie, or X-Men: Wolverine (though i actually had much to laugh about in this one, i saw it as an utter mess, but a funny mess at that).
Sure, now that Marvel scored big with The Avangers, DC think they "have to counter" with the Justice League or something like that and it feels kinda stupid and they will probably focus to much on Batman and so on and so forth; but hey, that's what this business is about and not just for Warner Bros., but for most of the entire business.
And in a way, this concludes to the point you got to in multiple of your last videos: What is the movie-/entertainment-industry gonna do about it? What do you wanna do about it? What is annybody gonna do about it? Right now it barely matters if a possible Justice League movie might suck or not, it will very likely get them the money they want either way and even if their "reputation" might increase or decrease a bit, by itself, the results won't change to much about the status quo, otherwise they would have to fail so damn hard, it is close to unimaginable.
That said, i just think this episode wasn't one of your bests either, but nonetheless, i'll watch the next one as well

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