This brings up a topic I very often wonder about. How hard is it for a "Leading Man" to really show his acting chops. Is that even what they're being paid for? I mean obviously you pay your dues with crappy bit roles, cheesy city theatre, etc. until you get lucky enough in a couple of auditions to get into movies and hopefully are noticed by someone. But once you've made it and are now in movies as a leading man, how much does your acting really deteriorate.
Personally I think there are a number of "Leading Men" actors out their who either have deteriorated badly or simply are given roles for who they are. Tom Cruise, Bruce Willis, Jack Nicholson, Al Pacino, Denzel Washington, and Kevin Costner just to name a few. I mean Costner sometimes doesn't even bother with Voice Coaching for roles that call for an accent. Jack Nicholson is pretty much "Jack Nicholson" in every movie he is in. Denzel used to be one of the best actors on the planet (Devil in a Blue Dress, Malcolm X, Fallen, Training Day), now his acting isn't anything to write home about (Deja Vu, American Gangster, Man on Fire).
Conversely I think the BEST actors are "Character" actors. These are the guys that fill those supporting roles and sometimes leading roles that just literally meld into their character where you honestly have a hard time telling who they are movie to movie. It took Pirates of the Caribbean for my wife to put a face to Johnny Depp even though he's been in (and been great) in like 40 movies before hand. "Character" actors like Kevin Spacey, Daniel Day-Lewis, Christopher Walken, Michael Caine, Hugo Weaving, Guy Pearce, Brendan Gleeson and Oliver Platt are guys I respect immensely but hardly guys who can carry a blockbuster on their own
There are of course guys who used to be "Character" actors and through sheer success have become their own personality. Like Brad Pitt, Samuel L. Jackson, etc. Which is where the conundrum comes in--as soon as someones personality becomes SO HUGE, they overwhelm every character they play, and they can't do what they're paid for (pretending to be someone else) at the highest level anymore.
Will Smith obviously is a "Leading Man" Actor and so I think beyond just his ability, that will hamper his performance for guys like Reality, I think. I will say that what he lacks in talent, he makes for in effort. The scene when he had to put down his dog was emotional and very well-done. But Like I said earlier, is 'Acting' really what Will Smith is being paid for or is he being paid to show up and be essentially Will Smith as the only man in New York? I mean replace Will Smith with say, Terrence Howard (someone who I think is twice the actor), is "I Am Legend" even half as successful?
Interesting question or am I two olives short of a greek salad?