I totally agree with you.
For many, tennis is at best a weekly outlet for some fun and exercise, and using a microscope to call a foot fault is just a waste of time.
My comments were mainly to younger and more fit players.
Maybe even there are some kids out there who will use their foot fault correction to learn how to get that squat/knee bend in the interval between when the ball leaves the hand, and when they actually form a bow shape in the trophy position.
They may actually get quite a few decades of a better serve, as well as correcting their foot fault, by making this adaptation.