An fine introduction to USB charging and Power Delivery protocols that also goes quite deep into industry approaches.

The presenter is from the automotive electronic parts market, and posted a great more recent (but more vendor specific) related video here as well:

• Introducing Richtek’s New Generation Automotive USB Type-C PD Charger IC
  • https://m.youtube.com/watch?v=0eHjBszMkXo

For example, I really wish my modern Anker AC charger would at least support "Smart Power Sharing Communication" with its Dual Port configuration "via Sinc_Cap", rather than naively having total output equally for each device regardless of each device's power profile capability.