I wouldn't put Arnie in the top 50 either. And I'm not talking about the others, I'm talking about Newman. Who, in his latter years, still knocked out the likes of Nobody's Fool, The Road To Perdition, The Hudsucker Proxy, The Colour of Money, The Verdict, Absence of Malice, Fort Apache The Bronx. And that's before you consider The Sting, Butch and Sundance, Hombre, Cool Hand Luke, The Hustler, Cat on a Hot Tin Roof, etc etc.
Ford has been sleepwalking through performances, giving the same one-note grumpy old man performance since The Fugitive , his last good movie (though I'll grant you that he was good in Crystal Skull, even if the movie blew). He's now 70 and hasn't been relevant for years - at the same age, Newman had just turned out Hudsucker and an Ocar-nodded performance in Nobody's Fool.