Hi

A good example of EAV model are e-commerce apps like Magento. They are using an EAV model and duplicate writes to maintain some denormalized tables, they are using EAV for writes and relational model for reads. You can also find EAV models in clinic models due the huge range of attributes to analyze. In my opinion, as you said in your article, business requirement standardization is the main reason for using it.

Regards

Carlos