Maybe "laypeople" in this context means "programmers with very basic/naive understanding of crypto and implications".
Most people on HN know what a "goto" is. We're talking about attention on the HN front-page after all.
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Also I bet most readers of Schneier's bug know what goto is as well.
I don't agree. Most people don't even have a basic understanding of coding. I think that it has more to do with the fact that there are about 500 million vulnerable devices out there, and that we are talking about Apple. Remember Antennagate, it wasn't even that big of a deal and look at what the press made of it.