Maybe, but the other side also needs to be cleaned. And the car side TX won't be anywhere near as bright as a street lamp (and probably IR) and will be more vul

Maybe, but the other side also needs to be cleaned. And the car side TX won't be anywhere near as bright as a street lamp (and probably IR) and will be more vulnerable. As you point out, all of this is likely surmountable, but... why bother if the status quo is serving the use case?