Your defense of Wolfe's ending reads to me like special pleading. How can you argue that we're supposed to take it as satire and also at face value? I grant you that there's nothing inherently implausible about a character at the end of his rope undergoing a conversion like Charlie Croker's. But the point is that Wolfe just tells us about it at the end, rather than persuasively depicting it. (And one more thing: The philosophy in question is a curious form of idealism in the first place. Stoicism, at least as explicated by Tom Wolfe, argues for a radical autonomy, and is antimaterialist only in that it holds other principles higher than material gain when the two conflict; it doesn't seem to offer the first piece of advice on the treatment of one's fellow man. If this be uplift, it's of a very Wolfean kind.)
I agree that Wolfe's fictional gift is largely about predicament rather than character, and I don't underrate that gift. But it's not true that all the great social-canvas novelists who dealt partly in satire lacked the same skill Wolfe lacks at creating what E.M. Forster called round characters. Everyone likes to think of Dickens in this way, as a novelist whose casts were divided between wickedly funny cameos and dreary examples of Victorian sentimentality. But it's not really true. Even in the roistering Nicholas Nickleby, the reader feels something genuine for poor blighted Smike, and for the suicide of Ralph Nickleby. No? Wolfe set himself the goal, in his famous essay, of using social realism as a way "to know what truly presses upon the heart of the individual." And it's this goal he fails, most of the time, to reach.
In answer to your last question, I think A Man in Full is set in the present day. Croker's predicament, Wolfe is careful to explain, arises not from some widespread failure of the real estate market, but from his own overreaching: He built his tower too far out into the suburbs, leading the market by several years; and his vanity made him overspend on a scale that even the liberal tenets of real estate banking couldn't tolerate. I found this credible. (Another reason it's clearly not the early '90s is that there's one tiny passing reference to O.J.)
Over and out,