Earlier quoted context omitted.
It's a consequence of consolidating on a single connector format. It doesn't make economic sense for every cable with the same connector to support the same power or data rates. Sometimes you just need a phone charging cable, sometimes you want to charge and drive a laptop at over 100w, and sometimes you need to carry 4k60hz hdr video over 10ft which is pretty dang hard.
So now we're in a world where the cables have different functionality, but you can't tell them apart. So you have to keep the cable with the device it came with and you lose the benefit of having the single connnector format entirely!
The end nodes vary in capability, but it's nice I don't have to fish out my crescent-ended connector to differentiate from my flat-ended connector because I needed a higher transfer rate.
One stack of USB-C cables lets me connect all my devices together. Whether they make sense connected together is up to me.