You are making some faulty assumptions here.
You assume there is a right way and wrong way to number the drivers. While you may personally find the duplicate numbers annoying, I'm sure there are plenty of people who prefer this to a scenario where the drivers are using incorrect numbers. I guarantee you that if they switched it and assigned different numbers to the F2 drivers who shared a number with an F1 driver, then people would come here and make bug reports about how their favorite F2 driver doesn't use their real world number.
So essentially all it's doing is swapping out one problem for another and for all we know changing it could result in more dissatisfied customers then the current system. You are a paying customer and that gives you a right to be dissatisfied and have your complaints heard but that doesn't give you the right to make demands if it comes at the cost of another player's experience.
The real solution would be for them to include an in-game editor so people could change the numbers how they like, but for whatever reason they have declined to add one despite several requests over the years.