[klempner]

Are you sure these "cheap vape pens" don't just use 5V3A, which doesn't require any PD negotiation at all? (a lot of them screw even that much up, and a lot of people confuse "PD negotiation" with simply having the right resistors on the CC pins)

There is real cost savings here -- the RPi5 avoided the need for a buck circuit, and for that matter probably a dedicated PD controller chip.

In contrast, in the context of a "cheap vape pen" you have a battery which means you need to be able to convert to (and from!) battery voltage, so you need that conversion circuitry anyway.