To the users of MILP libraries, the difference between algorithmic and hardware improvements are not so significant, and both can be called "Computing Power" in terms of number of application-specific solutions per second.
You're right, and your insight is illuminating into the real gains had by the world on the backs of hardware and software improvements, but I think you're one level deeper in the abstraction than the paper intends to be.
Then i must have phrased it badly. The fact that all the speed up would be attributed to FLOPs in the MILP case with that methodology means any improvement in data acquisition, management methodology, mathematical modeling, the ability to dig deeper or even the increased regulatory cost of boring which taken together sorta look linear when logarithmitized (for weather prediction or oil exploration (after a dubious data selection)) would also be attributed to computational improvement.
You're right, and your insight is illuminating into the real gains had by the world on the backs of hardware and software improvements, but I think you're one level deeper in the abstraction than the paper intends to be.