An ankle light that also shines forward and to the side may well help you with left turning on-coming drivers where most reflectors are not very effective. Yes, you don't encounter those left turners often. But the death rate when it happens is impressively high. And as no-glider pointed out above, that up and down leg light looks like nothing else out there. It gets noticed.
I rode for decades in the days before any good lights with just a good reflecting vest, minimal reflecting stuff on the bike and religiously, an ankle light. First decade around Boston. Never hit. (Yes, I put myself in a few situations a good headlight would have kept me out of. But the good batteries and bulbs hadn't happened yet. The bright systems were big, heavy and expensive. Night Rider's halogen headlight with the WB battery, real runtime, bright and reliable? I was on board fast.