This is just a personal theory, so take the requisite pinch of salt, but the UK did have a stronger Labour presence in the 20th century postwar, and was backed by the power of trade unions. The key difference in how it's worked thus far in the UK vs the US, is that in the UK, demands are set by trade unions, which are then fed directly to the party (or used to be before nu-Labour), which once in power can simply codify it into law. In the US, progressive laws are only made as a compromise after years and years of protesting, legal litigation, and callous, deliberate ignorance by the part of the ruling class who eventually might give in to pressure once the culture has overall normalized it too late. As for why it seemingly never progressed past second wave feminism, I cannot say. Complacency, or the lack of an effective union backing for demands after the Thatcher years destroyed what little remained of the SocialDemocratic Labour party of the 70s into the technocratic neoliberal monster it is today.
This is just a personal theory, so take the requisite pinch of salt, but the UK did have a stronger Labour presence in the 20th century postwar, and was backed by the power of trade unions. The key difference in how it's worked thus far in the UK vs the US, is that in the UK, demands are set by trade unions, which are then fed directly to the party (or used to be before nu-Labour), which once in power can simply codify it into law. In the US, progressive laws are only made as a compromise after years and years of protesting, legal litigation, and callous, deliberate ignorance by the part of the ruling class who eventually might give in to pressure once the culture has overall normalized it too late. As for why it seemingly never progressed past second wave feminism, I cannot say. Complacency, or the lack of an effective union backing for demands after the Thatcher years destroyed what little remained of the SocialDemocratic Labour party of the 70s into the technocratic neoliberal monster it is today.