I assume this Shredder will still be some sort of military guy. Not being a TMNT fan, that doesn't bother me at all. Does it bother you?
Though I'm not really a TMNT fan, it does kind of bother me that Shredder is being reimagined as an evil military officer. Mainly because it implies the movie is going to feature a villainous government agency as a foil to the heroes, which is something Bay has already done with the Transformers movies. Like I said earlier, it just makes the movie look like Transformers with giant robots replaced with sentient turtles.
I don't think he's prejudiced for it, I just think it's dumb and annoying to whitewash famously ethnic characters.
It is a bit disappointing that Star Trek, a franchise known for its racial diversity has now cast a white guy as an Indian character. Sure, the character is well known as being played by a Latino actor, so one could argue race shouldn't matter. But having a white guy does make things look less diverse all the same.