Dude, you aren't interrogating me. I'm schooling you.
'Culture' as a whole isn't a 'construct of porky.' (Notice meme-tier, again.)
And it isn't something the Frankfurt School proposes, really. Go back to Marx, hell, even earlier attempts at materialism. You call yourself a devout science fan, so you should also respect materialism.
The spontaneous beliefs we form about the world we live in obviously correlates with that actual world. If I live in slave holding society, with a certain set of technological advancements, etc. my art will reflect that, my thoughts will reflect that. Same goes to Feudalism or *gasp* capitalism.
Now to the 'porky' part. Turns out, that if you look at these different societies there was an obvious bias when it came to the spontaneous thoughts of the people towards their rulers, also it turns out that these thoughts weren't so spontaneous at all, culture, religion, art, even science were tilted towards their favor. If you look at how Feudalism ended and capitalism came about you'll notice that first the zeitgest changed: people thought of the lords and kings as parasites on the people. This was the pre-requisite for our societies to change over to capitalism.
Now if you were, back in those times, a king, a lord, an aristocrat, or an idiot who thought that he's interests align with his rulers, you thought that the great thinkers like Kant, Hegel, or even Robespierre were a conspiracy against the culture, the beliefs, the morals of the time. Well it wasn't. Everything happened right in the open.
Yes, they do.
No, you don't. It's established by now that you haven't read a single fucking book in your life. (Not that you could actually read in another language other than your own.)