culinary trend that eventually gets hopped on by brands and combined into their own products on store shelves.

For the trendsetting chefs etc upstream of that, I assume the humbleness of the biscuit and sort of related notions of 'authenticity' is/was part of the appeal. "Remember those grandma ass biscuits you thought were bad? Well actually they're good. I would know, because I'm the Real Deal."

I'd guess this process of bougie 'elevation' of a humble (cheap) foodstuff is also profitable under the right circumstances

They are good tho