that’s bizarre. Torx are commonly used in construction with impact drivers, and in vehicles as well. Very rarely are they ever problematic, and that’s with quite significant shock loading as well as torque application in the case of construction, i would imagine more than in a bike, but i wouldn’t be able to say off the top of my head, though they might be bigger standard head sizes, so that could be it.
Regardless, begs the question why hex screws aren’t in construction, those should be simpler and easier to produce.