I would not put any decent cable where it will be stepped on, could damage cable. That said Geortz, Analysis Plus, Nordost make flat cables. For reasonable cost Analysis Plus and Geortz.
If it were me and I had to place speaker cables where people walk over then I would use aluminum door thresholds and paint to match carpet, running cables under them, preventing damage to cables.
If it were me and I had to place speaker cables where people walk over then I would use aluminum door thresholds and paint to match carpet, running cables under them, preventing damage to cables.