I had long thought from the use of quartz glass in some UV environments, ordinary glass blocked most of it. Vehicle glass of course, is there for visibility purposes thus different / limited as compared to what's available for buildings. [1] [2]<p>It's quite common to see cars in Northern Australia with tinted coatings applied to the side window glass but it's regulated by law not to be too dark.<p>[1] Implication for photosensitive patients of ultraviolet A exposure in vehicles - <a href="https://pubmed.ncbi.nlm.nih.gov/15491429/" rel="nofollow">https://pubmed.ncbi.nlm.nih.gov/15491429/</a><p>[2] The role of glass as a barrier against the transmission of ultraviolet radiation: an experimental study - <a href="https://pubmed.ncbi.nlm.nih.gov/19614895/" rel="nofollow">https://pubmed.ncbi.nlm.nih.gov/19614895/</a>
Anti-glare coatings are not very robust, would not hold up well and they are even worse than glare when they get damaged. I have a vague memory that the UV protection in glasses is either a quirk of the plastics used or something done to the plastics during manufacturing and can not be easily applied to glass, plastics do not make good car windows which need good abrasion resistance.
Is UV 400 necessary? I don't think anything under 380nm goes through glass.<p>But for the most I believe it vastly more practical to put on sunglasses if there is too much light than needing floodlights in the night. Because then you want every photon get through your windows.