I think it depends on what you consider 'cultural stuff or knowledge' to be and if you think different types of knowledge are specialist or not. In our family we have what I’d call ‘LW/WC cultural capital’, which is our ‘cultural knowledge’ or 'stuff' that aligns us with others like us, but we’ve now expanded into other areas of knowledge that allows us to also align with other groups of ‘others like us’ of all kinds.
The LEA (and some of MN) considered things like mechanics, 2&3 phase electrics, welding, soldering, tool making, wood butchering, glass, glazing, driving, and basic animal handling, to be unsuitable subjects for my children.
But, art, sewing, pattern making, French curves, scale rulers, music, crafts, and food preparation were considered acceptable as having a place in their education.
When you look at it it's mainly the elevation of what was considered 'cultivated' by the landed gentry then copied by the MC's.
But culturally any child in this family would be effectively an outsider without all of the above as basic knowledge and skills, and any LDs aside, you'd be seen as a bit of a numpty if you didn't have them.
I don't think it's just about showing of a 'good' education, and 'in depth abstract conversations', because everything we learn about is likely to get used or applied practically somewhere in some way.
I'm totally self educated from a poor start and developing 'cultural knowledge' and references, make it harder for those in power to communicate over my head, which has allowed us to challenge the status quo.
The internet has been an absolute game changer, and concepts of 'high culture' and 'low culture' are evolving too. Knowledge is power.
I believe in society, sharing knowledge and ideas, and that education of all forms should be freely available to all.