Superheroes need to have a commanding presence. Idris doesn't just have that, he basks in it. That's why it's easy to make him first pick on every role, especially since he also got most of his peers beat in talent.
Yup. It's like asking "Why do you always want that prime
Michael Jordan guy on your team when there's countless other black basketball players known and unknown that you could draft? Why not give Boobie Gibson a chance?" ....
Yea.. Boobie Gibson, let's give him the keys to the franchise
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But really, Idris is stuck at Marvel. It's not happening, plus rumors are they are announcing a Hal/JStewart buddy cop route GL movie at comic con, which is in a couple weeks. So either it will be Tyrese or they've already cast an unknown that they'll introduce along with Chris Pine (as Hal) at comic con. Stewart is my favorite DC superhero, and I'd rather they cast an unknown like they did with Cyborg than Tyrese. But it's whatever at this point.