It's not even just that it's expensive: if you look at a cable that's full-everything including top-rating for power delivery, it's a pretty thick inflexible thing and not at all what you want for e.g. a mouse or a keyboard or whatever.

This isn't even new. Even USB 3.0 (the first gen, later rebranded as USB 3.1) micro-B to A cable, which has been around for at least 10 years at this point, is already not good for mouse. Nor is my USB-C 2.0 with 60W PD cable.

Which is fine. There's plenty of devices I own that just need a charging cable. But it's near impossible to know what cable does what. Even some of the expensive ones I've bought don't do what they say.

You would think with how much money is pumped into the governing body of the standard they could both force classifications of cables/devices and also verify they actually do what's advertised.

Every company using USB-C needs to pay $3500 USD to use the branding and a proper vendor ID. Every single company. And yet they still can't solve the very basics.

But then why make them USBv4? Just make v3 cables. Has it truly been politicized by the industry to add so much complexity so crappy manufacturers can sell bad cables/hardware with the latest version number instead of just making stuff that consumers can use?

But they can just continue making old USB2 cables

Nobody would buy their old USB2 cables when they can get other faster cables, so the manufacturers of the old cables would actually rather pump money into politically pressuring the relevant standards committee into 'massaging' their latest technical definitions to include products which already exist.

People buy USB2 cables all the time, and they're usually correctly labeled too.

But there's no profit to be made when everything new uses USB-C now.

Usb-c runs usb 2.0 just fine! And yet we still have companies trying to make bad USBv(n+2)