......Aluminum extrusion is for guarding and tabletop machines. Making actual industrial equipment out of it is bush league.
I have seen a ton of conveyors made out of 80/20 type material and if done right it has held up fine. It seems to be a versatile way of building things. It makes it easy to mount sensors & actuators on it.
It is also commonly used on all types of fixtures. Since I don't have to buy it I'm more or less neutral on the subject.