The only argument you need is the fact that being connected to the movies and TV severely limits whats possible in the games / creative freedom to do whatever with the world and story lines so long as it sticks to source material and makes sense for the characters.
Better if they are separate as it allows more creative freedom for developers. For example a Justice League would be severely hampered if it had to be linked to the movies as developers couldn't use the villains they want.
The only argument you need is the fact that being connected to the movies and TV severely limits whats possible in the games / creative freedom to do whatever with the world and story lines so long as it sticks to source material and makes sense for the characters.
Better if they are separate as it allows more creative freedom for developers. For example a Justice League would be severely hampered if it had to be linked to the movies as developers couldn't use the villains they want.
It’s the new K.I.S.S. principle. Keep It Separate Stupid.