Seems like if you do this over and over and over again under different brands - say on like a staggered Decade schedule - you optimize your profits, milking as much out of your market as possible while severely cutting cost and quality and competence.

Completely different thing. The gist of the Boeing theory is that it was ruined by a finance-driven culture that resulted in cost-cutting away quality and safety.

"Enshittification" is not based on cost-cutting or optimizing for profits. It's when a product that's already "perfect" and widely used, has lots of money/effort invested in it to chase further growth, and the changes end up making the product worse for its existing userbase.