I’m not sure it’s generally appreciated the extent to which Frederik Pohl underwent a sea change in the mid-70s, much as Silverberg had done a decade before [partly under Pohl’s editorship]. Pohl had been a significant writer in the ’50s, more of a significant editor in the ’60s, and then after a quiet period re-emerged as a major writer, an order of magnitude beyond his previous work. Initially with short fiction like “The Gold at the Starbow’s End” and “Shaffery Among the Immortals”, then with novels, first Man Plus (1976) and Gateway (1977), then with JEM and The Years of the City, with The Cool War and the Gateway sequels, and so on, with at least one substantial, if not always major, novel pretty much every year for another 25 years.
He was like Asimov, Clarke, and Heinlein, in that respect, all of whom had periods of silence in the ’60s and early ’70s until they reappeared with major works. As if to reassert the dominance of traditional SF after the passing turbulence of the New Wave. Not everyone welcomed their return. (I liked Gateway well enough, but at the time was more impressed by Benford’s In the Ocean of Night.)
I’ve read Pohl since the 1970 Ballantine release of collection Day Million, with reissues of several earlier collections, all with Escher-esque cover art by Ian Robertson. I only met Pohl twice, I think, once in ’78 at a book signing, because I have signed first editions of Man Plus and Gateway, and again about a decade ago, when I finagled my way to having dinner with Fred, his wife, and Charles Brown, on the last night of a convention, by offering to pay. (That works.) They were good conversationalists, as I recall, but finicky eaters.