Apparently, fans were surprised and quite frustrated that Grant Gustin's well-accepted take would not make the plunge into the film. During the interview with Wall Street Journal, Stephen Amell was asked if Green Arrow movie was on its way, should he have the first opportunity at reprising the role. The actor's answer is one with which most of fans will agree, particularly where Gustin's Flash is about:

"Yeah. Of course. And I feel like it should be Grant doing the movie. But the important thing to remember is just because Grant Gustin plays the part of Barry Allen doesn't mean Ezra Miller can't also play Barry Allen. There can be different interpretations of the character. Anyone who is a fan of the comics knows the Flash character is one of the forces that leads to parallel universes.

"And who knows, they might find a fantastic actor to play Oliver Queen on the feature side who has a different take on the character. I'm certainly a departure from the typical Oliver Queen from the comic books. I just think that everybody needs to be patient with the whole thing. The fact that DC and Warner have announced all these comic book features is nothing but good for business. It is difficult to me to want or envision an Arrow movie when we are shooting the 10th episode of our third season with 13 more episodes to go and in all likelihood 3 more seasons on the other side of that. "

As DC's TV universe has persisted to develop, Amell has taken the job of creating publicity on himself (including teasing punches at the antagonism), so it's no bombshell to heed him present a heartfelt response, followed by an explanation. Geoff Johns has also clarified his outlook that all DC content, TV or film, is a multi-verse just like the comics - there's no 'real' story of Oliver Queen or Barry Allen; merely ones that positive fans will like best.