Tbf thats not much of an argument. I can say I hate Avengers because they have terrible characterisations. Thats just a subjective thought, not an objective truth.
Thats the thing isnt it? Do readers care when characters are changed to fit a narrative in elseworld stories? No. Look at Red son. But the thing is, with Marvel choosing to put the "most popular" version of the characters on screen to celebrate them, when you create a DCU, you have to use the most popular version of the character for a cinematic universe. Think about it, if this was a seperate elseworld story. Just the JL trilogy(MOS-BvS-JL), seperate from all other continuities. Would people have been as mad? Not at all.
And thats considering if I say these characters have had some violent changes from the comics. Infact I would say these characters havent done anything in the movies that they havent done in the 75 years of comic history. Infact in the comics, they have done much worse. Who decides whats the "heart of a character". Who decides which version of the character is right? Nolan said it himself people are less accepting of variation in the Superman characters unlike Batman. I mean you have the golden age, silver age, bronze age, post crisis, birthright, all star, earth one, new 52, rebirth all different interpretations in major and minor ways. You cant say we all love one version and hate the rest. So what gives? Sure they can choose the most popular one. Or they can choose a one which allows them to tell the story they want. If we keep the characters the same stagnant "version people recognise and love", then there's no room for growth, and the character will die. Thats why these characters have always been re-imagined, and always will be. Some more popular some less. Wonder Woman needed its first move to be a hit, so they went with the most popular version. But when its the 8-9th movie for the character, a load ress travelled isnt the wrong choice.
But lets not pretend these characters have violated the comics, as if there is only one version like say Harry Potter. Because imo the writers seem to understand the canon and characters much much much more the some fans who claim that they dont. And lets not invalidate other's opinions using the "ad populum" fallacy.