Can I offer a counterpoint? Much like OG USB put a 5V supply within everyone's reach, USB-PD has made programmable, higher power supplies available to everyone. That's a big deal, because PSUs
are an expensive portion of a product, especially for small manufacturers and hobbyists. Having a dedicated standard that supports multiple voltages and currents allows small players to take advantage of the same economies of scale as the largest electronics manufacturers.
Case in point, IKEA will happily sell you a very well built 20W power supply that provides 5, 9, 12, or 15V for less than $5 here in Canada, and you can get a similar price from legitimate Asian distributors, even when buying in limited quantities. If you're working on a small-batch electronic product, that's a boon to your BOM; if you had to go out and source a dedicated barrel-jack PSU with the same capabilities, it'd cost much more, and you don't know what kind of quality you'd be getting.
Where the standard really falls on its face, IMO, is in its opacity. You can get a chip that does the PD negotiation for pennies, but there is no way to inspect the protocol without shelling out thousands for a dedicated analyzer, so when things don't work, it's really hard to troubleshoot the reason.
(Disclaimer: I'm working on an open-source protocol analyzer, so this probably colours my view on the matter a little.)