This part was confusing and possibly useless. The source oreilly article (https://www.oreilly.com/content/software-architecture-patter...) cites a web browser-based auction site. That doesn't sound very "data decoupled" to me when each browser needs up-to-the-second updates on bids.

They are better explained here: https://www.oreilly.com/content/software-architecture-patter...