> In my mind, besides the self declared objectives, frameworks solve three problems .. “Simplification” .. Automation .. Labour cost.

I think you are missing Consistency, unless you don't count frameworks that you write as frameworks? There are 100 different ways of solving the same problem, and using a framework--- off the shelf or home made--- creates consistency in the way problems are solved.

This seems even more important with AI, since you lose context on each task, so you need it to live within guardrails and best practices or it will make spaghetti.