But the left, represented as a class analysis method, has always had a tendency to a certain kind of social conservatism that isn't really that compatible with progressivism.
Yes, this is the Labour has "always been more Methodist than Marxist" point, which is historically true.
I would say is that the term "liberal overreach" is an awkward one because it confines any perception of the phenomenon to movements and resistance within the framework of the Overton Window. What this does is miss another important facet, which we are beginning to see in the UK, whereby ordinary people are starting to notice the political, social, financial and cultural opportunity cost of these liberal fixations in terms of the political realm and overall national governance.
To be blunt, this is the perception that the establishment greatly prioritises social justice or globalist issues over practical political matters that causes very acutely felt day-to-day stresses in people's lives: traffic congestion is a good example, as are viable school places or the availability of medical appointments.
And this perception does a lot of damage over time. After canvassing before and after the referendum, I strongly suspect it was also a key factor in the Brexit vote. There was definitely a strain in our area that people's reasons for voting for Brexit that came down to a demand for the political establishment to focus upon the practical political challenges within Britain itself: roads, congestion, housing, facilities, jobs, quality of life etc. And they processed that demand through voting for Britain to remove itself from a transnational political sphere, which, to them, allowed for political distraction and stood as an emblem of these liberal fixations.
A metaphor here would be that these Brexit voters were like angry tenants that wanted to lock their landlord in their flat so he would finally notice how the holes in the floorboards, the mould on the walls and the fact the boiler didn't work.
In this environment, any politician that even pays minor heed to practical challenges within the nation state itself is going to harvest votes, which goes some way to explain why pretty much no British political party has emerged as a front-runner post-Brexit, despite being handed the political opportunity of a lifetime.