I am sorry... but BB and SS are not the same. Sure SS and MGS1 kind be kinda silly. But BB always came across as a more serious, and also more traditional in a double 0 spy scenario. BB has lost tons of people, and has been betrayed countless of times. I don't expect BB and SS to be the same and feel campy all the time. I think GZ has it right.. he is torn and becoming a demon. His path as we know is on freefall towards bitter and angry.
Big Boss never came accross as more serious. He was even goofier than Solid Snake. Have you even played Snake Eater? We are talking about a fellow who believed glowing mushrooms would charge his batteries (It worked, though...)
MGS is taking a serious turn, and it looks like it'll be the best one yet because of it.
Yeah, you wish. From the trailers we've seen so far, MGSV still keeps the silly, over-the-top stuff the franchise has always had. So you are wrong.