Re: Burnham would come to dunce inane
It's a bit of both, plus a shift in political priorities. 2016 was the highpoint of Merkel's induced Syrian migration crisis – Germany broke EU law by saying it would take refugees. While, it's still a sore point for many voters, migration via Europe from non-Europeans was in decline from before the pandemic.
It's difficult to argue that the UK's economy has benefitted from leaving the EU, with all economic measures with comparable economies showing the UK has higher inflation, lower growth and a lower standard of living.
But I'd also say there's been a decade of politics obsessed with almost everything other than the good of the country: Milliband, May, Corbyn, BoJo, Truss, Sunak. This has turbocharged the resentment that, along with immigration, paved the way for populism in the first place. This is going to make it very difficult for any government until populism either runs out of puff, or demonstrates that it's at least just as useless.