Why is that? The phrase and intended meaning (innocent, potentially to the point of being naive) is 200-ish years old.
It fits the sentiment perfectly. Developers who exclusively think in terms of commercial internet are prone to thinking that everyone uses up-to-date browsers, and therefore OSs.
The world is actually messier than that common misconception.
Whatever alleged origin of that quote is, its present identity has been dominated by the TV show, which isn’t even current anymore and ended so poorly that its cultural cachet has eroded. But mostly it’s condescending as hell and thus marks the user as someone who both trafficks in cliches and enjoys patronizing others.
Pretty sure it was referenced in Game of Thrones which introduced it to a whole new group of people, typically more online than the origins of the phrase, and popularized it's use on Reddit/Twitter for being a hilarious and original way to condescend people