i've made a possibile idea. don't know if it's an solution, but it has practicability.
not my intention to go back to the 70's generally, but i've used it merely to show how small adaptations back then already resolve a big part of the issues, especially because the use of (real) windscreens back then.
you could take that windscreen and simply enlarge it by a good factor that will be enough to dodge away heavy objects.
technology has improved by lightyears regarding (transparant) polymer materials. i'm sure there is material available that is strong enough to withstand the strongest of blows and a thin carbon arc at the top of the windscreen would probably grant it extra rigidity to withstand even more force.
the frontal fin is there to allow a driver to escape even when upside down by maintaining enough distance so the windscreen can be moved forward (if that's actually neccesarily) to prevent getting locked in. obviously the top needs to be open.
despite knowning the effects of head injury, i however still maintain that the affairs leading to the actual crash like bianchi are the real deals that need solving, rather then just slamming on something on a car. I also maintain that i'm of the opinion that windscreens like this causes visability issues for the driver thanks to hot sticky tires, sand and oil.
I know a pitstop would clean quite a good margin but still i'm wondering whether it wouldn't cause a big effect without a wiper. anyway, if it saves drivers, it's to be taken with a smile.
anyway check these impressions, i've included a modern-shaped front to show it can also apply to modern cars.