DCFC does not charge "most EV" to 80 in 20 mins. There are some new ones that can do 10-80 in that time, but if you're lower than 10, or if you don't have a better-than-average late-model EV, it's going to be longer than that.

L2 charging usually happens overnight, but larger capacity batteries won't fill if you don't plug in early enough.

More realistically it is 25 if you are starting at under 10. For a Model 3, at least, which is pretty much the very definition of "most EVs"