Because a torx head screw is .... wait for it .... still a screw.
And btw., is a flat head socket called screwdriver?
I don't get this discussion anyway. What's the point? Is there still someone around who doesn't own some torx tools? If so, is it that hard to get one if your airbox uses torx headed screws? It's less than the filter. If you can't afford it you can't afford the filter too and you surely can't afford running a car in general.