I can’t speak to your personal situation or experience, but it’s important to caution against labelling people sociopaths because there are many variations of this scenario where that’s simply not the case. It can and will damage relationships.
It's one thing to get back to the review and say "hey I just noticed something I didn't noticed earlier, and I feel it's important to address."
It's another thing entirely to afterwards accuse the designer of oversight and proceed to claim that the oversight is so glaringly obvious and that you would never have missed it if you were tasked with the design. As if you didn't missed it yourself when you were prompted to give your feedback.
If this is a collegial environment where people are unlikely to get fired, then a "late epiphany" is unlikely to be strategic behavior. It might be unselfaware ego, sure, but it probably isn't a person setting out to screw you.
If this is an environment with internal competition and stack-ranking -- if this is Amazon, where "leaders are right", and you lose the ability to be seen as a "leader" if you ever acknowledge a mistake -- then absolutely you might see this as a nasty strategic behavior.
Compared to many other industries, Silicon Valley has more-competitive people, higher stakes, and shorter tenures. You are more likely to see this there, I think. And people who have only ever seen that environment will probably be more on the lookout for it. Hence the attention it gets in this thread on HN.