i think enfj for ethan hawke seems right. samuel l jackson i could definitely see. i don't know much about clooney to make a distinction between enfj Ni or esfj Si. he seems somewhat detail-oriented to me.
ben affleck as isfj makes sense to me, i can't tell if he's introverted or extraverted, but i wouldn't be surprised if Si was in fact one of his functions. he seems like he's somewhere in the past/in his head a lot.
oprah is evil and i definitely agree with estj. i hate her. barack could be anything, i would say entp seems like a good bet. tertiary Fe to articulate everything perfectly to whatever eye he meets, yet dom Ne to always avoid any potential trap or pitfall ahead. he's fucking intelligent on-the-fly, it's impressive. he doesn't pause like an introvert would. auxilary Ti makes him extremely capable of ready-at-hand detailed knowledge, can deconstruct and get to the essence of logical problems, he's great.
i don't know bono that well, tho i'd guess he's more enfj than infj. i don't see a lot of Ti presence in anything he does, Se seems more relevant as a tertiary function.
i'm not sure what my feeling on the prevalence of male enfjs, but to me it seems like there are probably some borderline infj/enfj males that muddy the waters, and it would come down to the development of Ni and the reliance on EITHER Ti or Se. more introverted types tend to develop Ni in a very different way than extraverted types, for whom it generally shows much much less.
i'd be interested to compare Ni in enfj and entj. i think that would help clarify the differences, since ESPECIALLY in males the infj/enfj discrepency is tough to see unless the person is overly expressed in writing, art, etc. behavior alone doesn't show that much, especially when it involves some type of celebrity status and the lack of psychological health that usually results.
i mean, billy corgan, bono, and ethan hawke all at times fluctuate wildly in the introversion/extraversion spectrum. healthy dominant Fe is kind of a mystery in nf males. it makes them so much more rigid in their ideals than esfj males, which is exacerbated by the fact that Ni types usually have ideals that RADICALLY differ from the conservativeness of Si guardian types.