Most devices are backwards compatible and will run at USB2.0 speeds. Almost any cable will work, just slowly. That's a pretty big advantage.
Since I don't have much of anything that uses the 3.0 speeds, having everything on one connector is worth it, it's a great charging port, it's great for 2.0 speeds, and you can do 3.0 if needed with some effort.
When monitors hopefully switch over there could be some confusion though. I would imagine they'll need to actually start using the cable marking spec, and things will get a lot easier.
What do you mean when? Finding a usb cable that can meaningfully connect your pc and monitor is difficult. Especially in the “grab a cable from the drawer” types of situations.
Especially if faster USB ever gets mainstream and higher spec cables become more common.
If you have a fast USB-C external drive you might be able to use the cable you got for that.
With dedicated monitor cables, they're not good for anything else. Unless you explicitly bought a spare, your only choice is to go buy one.
In the most common case the cable will probably come with the monitor, and one end will just remain attached to it, not much confusion there.
At the moment it seems people use a lot of C to HDMI or C to DP adapters, so almost nothing changed other that the device side connector no longer having a bulky waste of space or delicate microHDMI that always seems poorly made if you get cheap adapters.
The cable's form should tell you something about what it does. I shouldn't have to guess at what a cable is for when I pull it out of a drawer. $100 a meter just in case is ludicrous.
A cable should not be able to damage a device.
I thought these things were given and well understood.