"overall traffic safety" is not a goal for MHLs for bikes, or motorcyclists; or seatbelt laws for car riders. Your first paragraph's question is the only relevant part of that.
MHLs could increase my overall risk of cycling accident enough to offset any gain from wearing the helmet.
There are studies that show drivers go faster and closer to cyclists wearing helmets (vs those without helmets). That alone could increase the risk of deadly car-bike interaction enough to offset the gains from wearing the helmet.
Edit - either way, I'm all for separate, protecetetd bicycle and pedestrian infrastructure. That's the "real" solution here - get bikes and cars onto different roads and what drivers do or don't do ceases to be a problem (almost, we still get drunken idiots driving down our protected bike paths outside DC).
MHLs could increase my overall risk of cycling accident enough to offset any gain from wearing the helmet.
There are studies that show drivers go faster and closer to cyclists wearing helmets (vs those without helmets). That alone could increase the risk of deadly car-bike interaction enough to offset the gains from wearing the helmet.
https://www.bicycling.com/news/a25358099/drivers-give-helmet...
Edit - either way, I'm all for separate, protecetetd bicycle and pedestrian infrastructure. That's the "real" solution here - get bikes and cars onto different roads and what drivers do or don't do ceases to be a problem (almost, we still get drunken idiots driving down our protected bike paths outside DC).