Very fair and very true, and I am 100% in agreement with your points, I do not know of a single resource we can go to as an educational toolset that is based on real world products/experience. The problem is the industry as a whole is locked into these NDA type agreements (along with proprietary information) which prevent a lot of the complete schema sharing etc which would help people learn the best.
That said, some of the best things to look at are open source projects and research their pain points and highlights. That will many times point you to the tradeoffs they made in modeling and in code. For e-commerce things like magento and other open source solutions can be really informative, even woocommerce and how it shoehorns itself into wordpress can be informative as to the tradeoffs on highly normalized vs lightly normalized vs key/values etc.
That said, some of the best things to look at are open source projects and research their pain points and highlights. That will many times point you to the tradeoffs they made in modeling and in code. For e-commerce things like magento and other open source solutions can be really informative, even woocommerce and how it shoehorns itself into wordpress can be informative as to the tradeoffs on highly normalized vs lightly normalized vs key/values etc.