We do seem to be getting worked up... it is (I repeat) a negotiation tactic and it appears to have worked to some degree.
Precisely, it is a negotiating tactic, but a poorly thought out one at that.
It has been obvious to all and sundry that UK desperately needs a deal, otherwise they wouldn't have wasted the last 12 months (four years) not preparing for a No Deal. And in the event of a No Deal, they have wasted all that time.
They've tried stalling in negotiations, in the hope EU would walk away, that didn't work. Now they've tried threatening to renege on the Treaty, for the same objective, that hasn't worked either.
Now what will they try next? All that brinkmanship does is to a) delay the inevitable, and b) create more uncertainty, and c) reduce the opportunity for a better deal.
Brexit is going to happen, and all that Boris can do is to limit the damage that will be inflicted.