I think we're now moving a bit far afield from my original comment, so I'll try to get us back. I'll give an example of how Berger's Marxism leads him astray. He called the Impressionist's work "bourgeois nostalgic art", art for the elite. But the Impressionists were the exact opposite of art for the elite, they were revolutionaries against elite, academic art based on patronage. They painted for the public and the market, and their work showed (for what was the first time), ordinary people enjoying themselves in routine settings like a picnic or a restaurant.
Why does ideology force Berger to diss their work and minimize how popular and well-liked they were? Because they showed ordinary people enjoying themselves in the first mass society in the world in ordinary everyday settings. But Marxism says ordinary everyday society is oppressive and the people ground down by a brutal capitalist elite. He can't get himself to understand that Western European everyday life of the late nineteenth century was the best life ever for ordinary people anywhere in the world or anywhere in history, and the fact that they were out happily enjoying it in a civilized urban way was a new thing in the world, and depicting that was an important advance in art.
Why does ideology force Berger to diss their work and minimize how popular and well-liked they were? Because they showed ordinary people enjoying themselves in the first mass society in the world in ordinary everyday settings. But Marxism says ordinary everyday society is oppressive and the people ground down by a brutal capitalist elite. He can't get himself to understand that Western European everyday life of the late nineteenth century was the best life ever for ordinary people anywhere in the world or anywhere in history, and the fact that they were out happily enjoying it in a civilized urban way was a new thing in the world, and depicting that was an important advance in art.