I break down the whole story in the article and on the podcast, but here's a very high-level overview. The US was desperate to switch off analog TV broadcasting and get people to buy digital sets, with the expectation that analog TV spectrum could be auctioned to wireless companies for billions. Americans were vastly disinterested in upgrading to DTV, thanks to the foolish decision to combine the US DTV transition with a high-def transition.
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That meant that Americans couldn't just add a DTV tuner to their analog sets - they'd have to throw away their TVs and buy high-def ones.
No one wanted to do this, in part because none of the broadcasters were willing to create high-def content (why would they, when everyone had standard-def TVs?). Advertisers weren't willing to pay to produce high-def commercials, because broadcasters weren't broadcasting in high-def, and viewers weren't watching in high-def. It was a total vapor-lock.
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