I’m sure it wouldn’t be hard to implement that, but it might not be as effective as you would hope. The drivers aren’t looking at any indicator in the middle of a turn. They are completely focused on their entry speed, brake pressure, hitting the apex and when to throttle on. So any kind of flashy light or noise could be very distracting to them. Also they have flashing lights on their steering wheel already another flashy light might just get lost in the mix.