Since when is 19 less than 18mpg?
Besides, if someone decided their unmaintained e30 is worth $4500 voucher toward something that gets 24mpg, let them. Other than race cars, or something to fully restore, who would really want to go near an unmaintained one?
I doubt the program will do all that well, people who drive old cars eligible for the program are either a) doing it because they can't afford anything newer or b) don't WANT anything newer.