Because those were sealed, tamper evident brushed motors, but people still found ways around that.

Also so what is to stop people from running different tooth pulleys?

Example: someone puts in a 39 tooth diff pulley in a car that runs a 40 tooth diff pulley? Takes it from a 2.0 to a 1.9 internal. In a fixed timing and gear ratio world, this makes a huge difference. And don’t think people won’t (attemp to) do it. The tech guy is now going to have to know the internal ratio of ever make and model of car, and what every cars parts look like. But then again since just about everyone wanting this runs awesomatix, it should be pretty easy.