LK-99 will not be the material that is mass produced as an RTSC.
What LK-99 is, is a working example of an entirely new theory for predicting superconductivity.
Once the new theory is fully developed, it seems likely it will point to a bunch of RTSC’s.
It’s a race to develop the theory, confirm the best material, grab the feed stock supplies, mass produce it and build stuff.
It’s the dawn of the quantum age.