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I never knew that USB-C extensions are not allowed for a reason
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This is a most excellent place for technology news and articles.
If you want a more detailed explanation, USB-C is a small connector that was designed primarily for data transfer, extended power range delivery (240w) was essentially hacked on to the standard. Electricity arcing between the contacts on the connector is the biggest challenge with this hack, since the contacts are small and very close together, which could burn out the circuit board and start fires. For EPR to work safely, there needs to be a lot of extra components on the circuit board/female connector side, which there simply isn't enough space for on an f2m extension cable.
As for why USB-C cables are so short, it's simply a matter of physics, carrying high speed data over larger distances would result in higher losses and requires thicker conductors and more shielding, which is why you don't see USB4 Gen3 cables over 1 meter unless they are optical, and longer "charging cables" are only rated at USB 2.0 speeds, because more often than not they don't even have the USB 3.x data pins on their connector.
It's amazing for a "standard" that there can be so many non-standard ways to do it. Your explanation is great and just reminded me that cable tester tools are a really good idea to have at home. There was one in Kickstarter earlier this year, I think, that was a really smart idea. I don't recall what it was nqmed though. Maybe you have heard of it? I'll see if I can find it.
Regardless, there are some devices that really need a specific type of usb-c cable to function properly and/or not burn the circuitry. (i.e. Nintendo Switch, the original release model (though, they may have fixed it in later hardware revisions))
Edit: Found it! That cable tester that I was referring to was called the BLE CaberQU. I think it is a really neat idea.