I could go into detail, but having that drown in an EVO thread isnt the best idea
In Injustice the complaint is self explanatory, even the announcers have a hard time being able to tell whats going on because of the Art Direction, thats basic.
In Marvel, I can follow the match fine, I said it was hard to
watch. Meaning its not pleasant, it doesnt look like a nicely choreographed fight like in SF IV or KOF, its a bunch of characters doing super jumps in and out of frame and OTG OTG OTG, its visually annoying and thats due to the gameplay flow.
And yeah, of course many people will like it, its a popular game with a fantastic IP and a long legacy of games. However, popularity has little to do with quality (I was very surprised to find how many young fans Sonic 06 actually has)