I very much doubt that. as long as the film is well made, most of the general public really won't care who's in it. they'll have questions and will ask those questions in regards as to why certain characters were used, but they won't obsess over it and complain ad nauseum online about how "Aquaman" or "Flash" wasn't used to their liking.
That's an idealistic view of the world, and especially the internet.
If it was a Doom Patrol film, they wouldn't care who was in it. You could make a Doom Patrol film with Solomon Grundy, Swamp Thing, and Jimmy Carter. They won't care. They'll either see it or they won't, but they won't think much of the roster. Why? Because "Doom Patrol" says nothing to them. It might as well be a movie about an insurance agency; nobody's gonna get mad about it.
Now, the words "Justice League" DO say something to people. They say "big superheroes get together". Bear in mind that the great majority of the film's audience never watches cartoons because cartoons are automatically stupid. To most people, The O.C. is better than any cartoon by default, simply for not being a cartoon. Anyway, the JLA is a known concept, so by so much as making the film you can guarantee two things are gonna happen:
1) A lot of people are gonna watch it. 2) Some people are gonna get mad at you.
Whatever you do, SOMEONE's gonna get mad at you if you're handling a known concept. Why? Because if the concept is known, people have an idea about it. And if they have an idea about it, they don't like it when that idea is contradicted. The guy who thinks The Bat-Man is a metaphor for anorexia got angry at the first Bale movie because it didn't have a clear posture regarding eating disorders.
With a Doom Patrol movie, the risk of angering people is so low, you can do whatever you want. But if you're making a movie about a known concept, and you intend to make lots of money off it, then you HAVE to make sure you don't contradict people's idea of it. In this particular care, that idea happens to be "big superheroes get together". If you contradict any part of that general idea, a LOT of people are gonna get angry and whine about it.
By the way, I'm aware that none of this says anything about the objective quality of the film... but let's face it, that's not a very important subject these days.
