You don't read ten lines, you decode them. If it's ten simple lines, decoding them is easy. If it's a nested ternary, it's a lot more cognitive load - unless you're used to nested ternary expressions.
However, I'd say it's a fair assertion to make that most people aren't used to reading nested ternaries.
And I think that's what Go (and this presentation) is about; you shouldn't need to get used to a certain code style to be able to decode it. You should be able to open up a file and not be surprised. If I were to come across a nested ternary, my first reaction is a raised eyebrow and a "wtf?". The wtfs / hour is one of the metrics that Go language is based on.