I think the biggest challenge will for the 40% of the population that does not have off-street parking at home. With average mileage of 7,800 miles pa (per the AA), most EV users will only need to charge twice per week. But I think it will take a long time before new EV users don't want to plug in all night, every night 'just to be certain'. Twice per week for the 40% means sharing a charger at work, using a rapid whilst near to home and a mix of some local over night charging spots. I think we will see quite a few developments in this space and I expect to be surprised at how this ends up in 2030.
"40% of the population" is a meaningless figure. What you should be looking at is what proportion of the car driving
population has access to off street parking, that is what really matters, and that figure is quite a bit higher.
If someone in London in a terraced house with no access to off street parking (or quite possibly no access to nearby parking at all) can't install a home charger that's irrelevant if they don't have a car in the first place or don't even have a drivers license. There are many places in the country where it's not feasible to own or drive a car, and there are also a lot of people who don't have a license and can't drive or don't even want to drive. These people are not suddenly going to go out and get a drivers license to drive an EV when they never could or wanted to drive before.
My mother in law lives in a terraced house without off street parking (although if push came to shove she could convert her front garden as a few of her neighbours have) but she doesn't own a car, doesn't drive, has never had a license in her life and has no intention of changing that. There are a lot of people like that.
Just count the people who do have cars and drive and the situation is a lot better than it seems from a simplistic population figure.