As I think about it, that face is reminiscent of Clint Eastwood. If they were to do a cartoon "Man With No Name" trilogy, I could see him looking like that.
i think it's just the style. with the neca turtles they pulled it off just right by nailing the look of the comic. this version looks like it didn't lean either way. not stylistic or realistic, but a blend of both which just doesnt translate well