The recent history of PG's twitter outpourings has been about the danger posed by political correctness and progressives more generally, in the face of criticism of things like AI bias.
I think he argues that progressives are a misnomer, political correctness a compromise with orthodoxy.
Progressives don't necessarily agree with other progressives. At least a subgroup wouldn't self describe as such.
This was tried to communicate very often, for example with reference to diversity of opinion. It was, perhaps with some reason, seen as an argument against diversity of skin colors.