The "this will fail social norms" card has been played many times, and it 
    has come to pass, but it hasn't been the core of a product failure.

Yes it has. The first cell phones, the first PDAs certainly fell into this category and only later when they became less obtrusive did the gain any real traction. Outright failures are less memorable because they tend to not get very far: people realize they are a mistake before they get to market. But a couple examples I can think of off-hand:

WebTv: Not socially ok at all to treat your TV like a computer. Still not, really.

Delorean: Weird car with its gull wing doors, too different, can't be seen in that.