small screws in general are just easy to strip. Small torx is also liable to breaking a driver, like most small screws and drivers.

Torx though, i've never had strip out once, even doing construction with them. Phillips on the other hand, they kill screws constantly, and the bits themselves get all chewed up causing all kinds of problems. Torx bits still look fine though.

Torx aren't exactly tapered, so they much less of a problem with stripping, compared to any tapered design, because tapered designs have issues with backing off.