And yet, they moan about your light, not your presence, which is what the few haters that I encounter do. "Aimed downwards as far as I dare" really does make it sound like the light is a torch strapped to a bike, not a bike light shaped for road use. Maybe, just maybe, there's a sound reason why people object more to having torches shone at them than car headlights? If you're wedded to the light, vertical fresnel lenses are available from the likes of CandB-seen and I guess it should be possible to make a cutoff shroud if there's no suitable ready-made one... or you could just get a proper bike light... or more likely, you'll keep on claiming it's somebody else's problem.