Yeah some of his believes are wrong, but this isn't one of them.
Michael Moore seems to exemplify this perfectly. He holds strong opinions on a wide variety of (often orthogonal) topics, yet Americans seem to feel the need to either embrace everything he says as good, or be vehemently opposed to him on the basis of their disagreeing with him on one topic. Is it too hard to say "I agree on this" and "I disagree on that"?
In thinking why this is, I have the following to offer: if it was "John Q. Random on Why Software Companies Die", there is a good chance it wouldn't rise to the top of HN quite so quickly. The accumulated reputation Card has is actually important for people reading this article. If this is so, then we must remember some of his reputation is being anti-gay-marriage: it is no less important to this article as is him being the author of Ender's Game.
This is in jest but most of the time external beliefs don't matter to the topic at hand. Such as do you discredit the work of Schindler because he was a womanizer and from most accounts a jerk, or look negatively on others who write about coding because when they aren't writing about coding they are out supporting the tea party perhaps.
A review I read of his recent story collection said his recent stories didn't have to try so hard, he knew they'd get published and he was more or less keeping a hand in, his earlier work he's working hard and striving for quality, this applies in spades to the rest of his recent work and may well apply to any entity's (sometime) fall-off in effort or innovation after they've succeeded.
His early works were written when he was still relatively young and passionate and had years' worth of crazy ideas swirling around in his head. Fast forward 25 years, he's written all the good ideas he originally had, and he's now a middle-aged Mormon father and conservative political activist. If you read his books nowadays, you'll find they're pretty much what you'd expect from that description.
He really hasn't written anything that good since the late 90s.
The Red v Blue wars in America? Weird. The latter Enderverse novels could have been cranked out by current AI. Treasure Box? Enchantment? Snoozers.
"Ender's Game" in '85 and "Speaker for the Dead" in '86 — It's hard to decide which one was more awesome. They're very different, but both are really gripping and create two fascinating worlds. When I read those two books, I thought I had found my favorite author of all time.
"Xenocide" in '91 — Sadly, not as good as the first two, but still a pretty compelling book. Veers a little too close to becoming a paean to the wonders of marriage and fatherhood, but constantly course-corrects and is pretty successful overall.
"Children of the Mind" in '96 — It's a readable novel, but as the conclusion to the previous three books, I couldn't help but ask, "WTF?" It's way too involved in its own ideas to bother with compelling characterization, and it has this weird tunnel vision that essentially reduces all human interaction to marriage, divorce or some analogue for the two.