You are correct that electric cars are not inherently more aerodynamic, but in practice it is easier to engineer them to be more aerodynamic. Not needing a big intake grill at the front makes a substantial difference, as does being able to easily seal off the bottom of the vehicle with a smooth flat surface.

Intake helps, correct, but on the latter point, most newer cars are coming with removable underbody paneling for just that reason. Aero is just improving across the board.

The Nissan Leaf, for example, has a drag coefficient of around .28. While that's good, it's in the same ballpark as the current ICE Honda Fit.

Oh yeah, you are right to criticize the Leaf on that front. You would think if they were going to make a really weird looking car like that, they could at least take advantage of the relaxed design constraints and make it super efficient...

The Tesla Model S on the other hand clocks in at 0.24, which is literally the best you can get on any production car right now. Admittedly this advantage might be partially cancelled out by the larger frontal area, but I think it's still noteworthy.