Canopy distortion
If it's going to be thick enough to protect F1 drivers from flying debris at 200 mph, there will be an optical impact - introducing curves to perspex and, to a slightly lesser extent, polycarbonate, will produce some distortion. In general, the more you pay the less the degradation, but there will also, inevitably, be a light attenuation issue whether or not the canopy is curved.
F1 drivers are bound to be sensitive about any apparent adverse effect on visual acuity - do they need to be? It depends how safety vs potential minor visual degradation is rated. After all, we managed cross-cockpit formation in the JP (dreadful), the Hunter T7 (much worse) and night rear seat landings in the Tornado (appalling). However, in F1 cars at closing speeds even the Buccaneer airbrake couldn't cope with, I might be a bit hesitant about another potential distraction as well.