> This is true, but neither is "tensile strength" really a thing for the same reason. Well, not the same reason. Shear strength is in many ways more important

> This is true, but neither is "tensile strength" really a thing for the same reason. Well, not the same reason. Shear strength is in many ways more important because failure usually propagates from an origin like a rip- by shearing. But fundamentally, tensile strength and shear strength are both much more empirical than compressive strength. Tensile strength can be used with ~99% accuracy on a wire that is microns long or miles long. If you double the relative width of a testing sample it will dramatically change the measured compressive strength even without buckling.