Less than 35% of people in the EU live in detached houses. A sizable percentage of these either rent or don't have enclosed parking.
My guess is that only about half of the population, once you factor in people who live in apartments but have separate enclosed parking spots, have the opportunity to charge an electric vehicle at home. This is probably optimistic.
However, once you consider that the ratio of apartments and alternative housing <-> detached houses increases in highly populated areas, I wouldn't be surprised if the percentage of people who live in an urban area, are able to spend 20-30K+ on an electric car, and have access to convenient overnight charging is significantly less than 50%.