HV is catching on the emerging 1/8 electrics. Many are running 6s lipos and lower KV motors to keep things nice and cool for really long run times. The demand for this is prompting the Mamba Monster Max, Quark, Tekin, and other mfgs to make ESCs for higher voltage.

1/10 cars don't seem to have the same overheating issues that the 1/8's do, so the need for HV just really isn't there. Most 1/10s run very well on 6 or 7 cell nimhs or 2 cell lipos. Someone might want to try a lower kv motor on 3s though for really really long run times. I can get 45 minutes out of my 3s 8000 pack in my Rusty VXL geared to the moon, so if the motor was a lower KV more practical for the track, I probabyl could run well more than 1 hour 1:15 straight with no problems and practically no heat.

The other issue is cost and availability of charging equipment. Higher volt batteries are not cheap. The market is heading in that direction, but it will take some time.