It’s of poor quality (the rubber of the cable on mine is turning into a sticky mess) and entirely passive.
Maybe ten years back, a whole ton of consumer electronics were made with some rubberized coating which felt great when new, but over the course of several years, degraded into an incredibly sticky mess.
I had a Grundig shortwave radio covered in the stuff. A couple of other gadgets.
Eventually, after I went to a lot of work with different substances, I discovered that isopropyl alcohol and some elbow grease could get it off. Didn’t look or feel great anymore – just plasticky, no rubberization – but it was a lot better than being sticky. But if this is the same stuff and it’s just a cable, I’d probably just replace the cable.
The main reason why this happens is the “soft touch”, rubbery coating that gets put on plastics is a substance called “TPE”.
TPEs are popular for this sort of thing because they’re quite cheap to apply, look and feel good and quite importantly compared to genuine rubber coatings, don’t smell bad.
The problem with TPEs is that they experience a chemical reaction when exposed to oils which causes them to degrade into a goopy-sticky mess.
The way to avoid this happening prematurely is to ensure that your hands are clean when using your mouse/headset etc., both bodily oils and environmental (food etc.) oils can and do affect the TPE.
It still happens after some time: I bought a rangefinder in a sealed plastic box at a fleemarket and it was somewhat sticky. It was the kind of welded box that needs scissors to open it and it was manufactured only a decade ago.