Two points though:

-They seem to have used a tiny multiplier. That's OK if we reckon that we'll soon be back to something approaching full employment. For te reality-based community however, I would expect a stronger one for a long, long while (this helps wind)

-For the UK, even today, yes there is a high domestic share, but gas is a world market. If UK gas is cheaper, then reducing consumption should simply increase the domestic share, not reduce UK gas production. If it's more expensive, why would the new plants use UK gas?
So I don't find this bit all that convincing, it feels like applying an average value to a marginal event. Plus, increasing UK gas consumption would speed up the depletion of the resource, which should carry a cost.

So my guess would be that the real situation is actually already favourable to wind even in the UK, and will be overwhelmingly so in the near future.

Earth provides enough to satisfy every man's need, but not every man's greed. Gandhi