That's (basically) what the charge limit already does; nobody's running out to their car at 2am to unplug it before it hits 100%.

Presumably these "it's a lease" folks are just choosing to set the 'limit' at 100%.

I agree with other comments that I prefer the regen anyway; it's weird to charge to 100% and have to use the brakes to slow the car so much. Your efficiency on that last 10% of charge is lower because of this lack of regen.