Out of curiosity, will that atrocious "this device may not be supported" box FINALLY be dead? I haven't used an Apple device for a long time, but that was one of my biggest pet peeve.
Hard to say. A LOT of USB-C cables don't meet spec and are either hot garbage or a risk waiting to happen, even if it's not immediately apparent to you as a user of them, based on the testing that Benson had previously done.
If Apples devices can detect this, you may get an error. People are already ragging on the cost of Apples USB-C cables, but to my knowledge, they all meet the spec and will also 100% work at 100W of charging and the other auxiliary items in the spec that most manufacturers seem to just ignore.
Now, with all that said, I'd never pay Apples price for a single cable, but if you absolutely want a cable that's going to meet spec, I also can't fault you for buying one either!
What are they charging? A standard non-apple 5 amp cable is $15-$20 for a good one. People think they're cheaper because they're used to buying junky 1.5 or 3 amp cables that don't even meet the USB-C spec for $5 on Amazon. If you're using a quick charger and your charge times haven't changed, you're using a cable that doesn't support enough amps.
I thought it was 30, but it looks to be 20USD, which like you said, not a terrible price by any means. I usually get the 100W capable ones for around 10-12 when they go on sale, so I even retract my "I wouldn't pay their prices" comment since I have paid 18-20 when I needed a good cable ASAP.
People just like to complain about the "apple tax" and I can't fault apple for not trusting their brand to shoddy products because the news isn't going to report that a shitty cable burned down a house, it's going to be that an iPhone burned down the house.