There is a reason why room temperature (ambient pressure) superconductors have been one of the holy grails of physics for such a long time: the implications are profound.
I used to be a particle physicist, and some of the more complex systems were just those used to cool the superconducting magnets down to cold enough that they become superconducting. If you can do that at ambient temp, you don't have to bother with that entire system.
Also: fusion reactors rely on superconducting magnets (or if you are JET live with the fact that you can only run your magnets for a few seconds before the overheat), so can have a large impact on future fusion reactors.
I'm already rooting for CFS' Sparc over ITER anyway. ITER is too big & expensive, if Sparc works it's an indication that we can build fusion "on a budget", too.
Idt CFS will care because they've already sourced much of the HTS tape that they need and their schedule doesn't permit waiting for LK-99 to be proven/disproven and all the years it will take to produce LK-99 in bulk anyway.
It's so insanely cheaper, because not only do you not need the cryogenic cooling (and all the support and maintenance systems and consumables like helium or nitrogen or whatever), but LK-99 is made from relatively common elements versus rare earth elements.
I used to be a particle physicist, and some of the more complex systems were just those used to cool the superconducting magnets down to cold enough that they become superconducting. If you can do that at ambient temp, you don't have to bother with that entire system.
Also: fusion reactors rely on superconducting magnets (or if you are JET live with the fact that you can only run your magnets for a few seconds before the overheat), so can have a large impact on future fusion reactors.