Not so sure the shift in the Tory party is down to the unknown unknown that is Covid. The Tories indicated a change of tack to turn the red wall a permanent blue just after the election. It seems to me that the Tories know they will need to change their emphasis on spending to visibly advantage to red wall areas and make some nod to increased tax on the rich to pay for it and for the sheer optics.
If so, I don’t see how, come the next election, Labour can make spending promises that challenge the Tories without very shouty headlines about Labour returning to Corbynism.
On spending at least, the Tories have undoubtedly moved towards Keynesianism, so the question of where that leaves Labour is, it seems to me, a valid one.