> unless they are upgrading from another USB-C laptop.

Which MacBooks have been for almost a decade - the 2016 MBP with Touch Bar was the first that went fully USB-C PD. Anyone who has had a MacBook in that time frame will have had at least one high power USB-C PD wall wart.

The Windows world, as usual, has been different, but even there, I'm not aware of any mainstream model being sold in the last two years without even a single PD capable port.