So, I take it you are not working in the field? Take whatever field you are working in and whatever you like the most about it day to day. Imagine having it taken away from you and no prospect of getting it back. Then people on the internet yell at you: You should have never wanted that in the first place, stupid.

Mathematics produces concepts and produces proofs of theorems. Up until now, the two things things fed into each other - you needed the concepts for the theorems and the theorems for the concepts. Now you can just prove theories without caring about the production of ideas.

Consider also, math produces the intellectual "tooling" for science in general. As I understand it, the important of grand unified comes because physics want an unified abstract conception of physical laws and thus a grand unified theory aims to be a unified mathematical understanding of the world.

I mean, as a though experiment, suppose a company produced a machine that simply predicted events in the future without giving any explanation of why. It didn't tell physicists whether any of their ideas were true or false, it simply answered question like "will this building fall down", "what will the spectrum of this star be", etc. It gave all the information of physics but discarded laws - physicists might find this a bit unsatisfying, especially if the machine was going to put them out of a job.