The difference between USB-C 3.1 (SuperSpeed+) and USB-C 3.2 (SuperSpeed++) is NOT different cables.
USB-C 3.2 implements in software that all USB 3.1 lanes can momentarily be used for a burst of all inbound or all outbound data transfer, momentarily doubling the speed.
USB 3.2, released in September 2017, replaces the USB 3.1 standard. It preserves existing USB 3.1 SuperSpeed and SuperSpeed+ data modes and introduces two new SuperSpeed+ transfer modes over the USB-C connector using two-lane operation, with data rates of 10 and 20 Gbit/s (~1.2 and 2.5 GB/s).
Ref: en.wikipedia.org/wiki/USB-C
Cables
USB 3.1 [SuperSpeed+] cables are considered full-featured USB-C cables. They are electronically marked cables that contain a chip with an ID function based on the configuration channel and vendor-defined messages (VDM) from the USB Power Delivery 2.0 specification.
Cable length should be ≤2 m for Gen 1 or ≤1 m for Gen 2.[9]
Ref: en.wikipedia.org/wiki/USB-C
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Other information from similar sources suggests that USB-C cables used at top speeds for DISPLAYS should be limited to under 0.8 meters for Apple brand top-quality USB-C cables, or 0.5 meters for other brands. Or use certified Thunderbolt cables of those lengths when connection to displays, or to Docks that will support displays.
There are some longer much longer (up to 4 meters) USB-C and ThunderBolt cables that seem to be FAR too expensive for what they offer (over US$125) These cables typically contain signal Re-Drivers, used to extend the acceptable length of cables and still provide top performance.
