“Parking Lot WiFi” isn’t going anywhere, at least for now. This article describes 3 real-world deployments of emergency ad-hoc WiFi, all with the goal of connecting students and families whose access to the internet has been affected by the COVID-19 pandemic.
Also, the Information Technology Disaster Resource Center has landed ~$2 million in grant funding and millions of dollars in hardware donated from AP manufacturers, allowing them to deploy around 375 ad-hoc WiFi networks so far around the country.