Was there ever really a time when this was de rigeur? I certainly feel it should be, but I've always felt alone having an intense interest in this as a dev.
I can't really speak to the first question, but I know of a small handful of people (who are developers or software-adjacent) who are deeply familiar with nuanced GUI details and can consciously talk about them. Plausibly, many people have historically not noticed many of these details, but got them for free when most software was built with native controls … and because they were rarely noticed, they rarely get explicitly specced for UIs built on less-robust primitives.
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