I think that the answer to the question in the OP is to look at what has always been solid Tory territory and understand what is happening in places like Guildford, Godalming and Horsham and villages like Steyning in Sussex.
The population in these charming towns have always identified with the conservative values, and these people are generally “pretty centrist, pretty moderate, very tolerant, pro-European, pretty compassionate and reasonable and very well educated” ( Follows)
This more or less sums up my children’s neighbours and friends.
But what they have been witness to is the Tory party moving more and more right wing as well as tearing the country apart in the name of a disastrous Brexit - for which most of them did not vote. The culture wars are not playing out well either, particularly with my grandchildren’s age group, and I suspect that they will never contemplate voting Tory as the political party stands at present.
I’m not sure that the Tories will ever get their vote.