No, everyone is entitled to their opinion. I will be offline the next few days and so do not have time to really get into this subject - except to say I would not be the only one to say that although you and others have come to similar conclusions, there are others (including myself) who are completely familiar with his published works, fiction and nonfiction, who would say that these views are superficial and incomplete - and, in large part, factually inaccurate - especially in the context of his complete body of work and with an understanding of his very pragmatic and libertarian philosophies.
Sure, retreat to relativism in the absence of evidence or compelling argument.
As it happens, I've read a lot of Heinlein, from
Red Planet to "The Roads Must Roll" to
To Sail Beyond the Sunset.
I will grant that Heinlein's early work is compelling and important as a contribution to science fiction. His "Future History" stories are really cool, and I have fond memories of devouring his "juvenile" fiction.
But something happened to
Stranger in a Strange Land between the time he wrote the first half of the book (a somewhat compelling premise in line with his earlier work) and the time he wrote the second half of the book (a bizarre act of wallowing in self-indulgent wish-fulfillment fantasy and pseudo-philosophy).
Unfortunately, he seems to have spent the rest of his career spinning out more self-indulgent fantasy, up to and including "arguments" for the benefits of incest, and the advantages of time travel in facilitating said incest.
But step back to
Stranger. It's fairly clear, as I noted, that Heinlein identifies with Jubal Harshaw, who becomes the mouthpiece for Heinlein's "philosophy." All he has to offer, though, is a bizarre and regressive variant of libertarianism that falls just short of Rand-level sociopathy, combined with the most conventional patriarchy imaginable.
(And before you ask, yes, I read nearly everything Ayn Rand wrote, back in the day, and tried really hard to believe it and defend it for about two years. I grew out of it, though, and am feeling much better now, thanks. I suspect Heinlein's "philosophy" is a lot like Rand's, in that it's the sort of thing you're supposed grow out of.)
Harshaw himself is constant in his objectification and subjugation of women. They exist for him only as pretty objects for him to ogle and to use, and the more of them the better. He is the very embodiment of the male gaze and male privilege.
Heinlein's regressive thinking doesn't stop there. Far from it! Why, at one point, one of the
women in the book argues that, if she's sexually assaulted, she must have brought it on herself!
To turn to this book as a model for polyamory, a model of how human relationships should be, is simply bizarre.
Oh, and in response to your claim that Heinlein is "universally" regarded as a genius whose every scribbling is a towering monument of literary merit, I need simply cite an example of informed dissent from that view:
http://www.sfreviews.net/grok.html. (tl;dr? Here's a quotation: "It turns out the haters are, by and large, right. This is crap.")
or Kinsey?