It looks like a Tesla Model 3 charges faster with a supercharger than the older Nissan Leaf.
The data above is with the Leaf for a full, 97% charge. My daughter says that for a partial charge, the commercial charger added about 60 miles in the first 20 minutes, and then slowed down. That's 3 miles added per minute of charging.
The Tesla Model 3 gets 263 miles per charge. With a 150 kW supercharger, it gets:
50% charge after 20 minutes. That's 7 miles per minute.
80% charge after 40 minutes. That's 5 miles per minute.
Suppose you want to drive 600 miles in a day, which is about my limit. You start off with a full 263 mile charge. You have to add at least 337 miles, but actually more like 370 because you don't want to arrive at the destination with zero charge. So that's about 74 minutes of waiting for the supercharger to reach 80% (5 miles per minute). You can eat lunch or rest while that is happening, but I think that is considerably more time than I usually spend eating and resting when I drive 600 miles. To fill a gasoline car enough to go 600 miles takes only a few minutes.
If superchargers can be made to go faster, or if the range of electric cars reaches about 600 miles, this problem will be largely alleviated.