I think your math is off some how. I have a Model 3 and two Leafs and we charge them from our 39 400 Watt panels without trouble. They are always ready to go fully charged unless one of the boys has been doing more than normal of driving to the beach with a girlfriend and then borrowing the Model 3 for a concert, or whatever fun involves using all the stored energy at the same time (e.g. not commutes to school or work).

It takes about a 6-8 hours to charge my Leaf on a small solar install.

But yes, it needs to be sunny if that’s going to be pure solar.

There are many hours in a day and EVs are pretty efficient. You might struggle if your goal is to drive 200km per day but if all you want is to drive to work or go shopping, you'll be fine.

What? My BIL’s installation is small, roughly 8kWp, on sunny days he easily gets 40-50kWh, if not more.

because solar panels only exist on houses?