Or has red wall left because connection to grassroots/unionism has been lost and the memory of Thatcher has faded enough that the stigma of voting blue has been removed?
Also the misplaced belief that "you've done fuck all for us" by not preventing austerity
People vote for what motivates them. Caring about people, thinking about how to make the world better for all, having a more caring society which looks after you. It's not an easy sell in to an environment where it looks like nobody cares.
Red wall left because "you've done fuck all for us" and have gone Brexit / Tory.
BLiar mob left and probably went libbdem/Tory
Blair did wrong went green. After libbdem dalliance.