It's a shame it's so hard to make a USB-C Power Delivery condom. The small nubber of USB C chipsets don't support it so anyone trying it is in for a ton of complicated implementation.

(PD uses the data lines to negotiate power capabilities and requests, so you can't just cut them. Instead you have to implement a little bidirectional firewall. I'd bet you could sell a lot of them, but probably not enough to justify the effort)