Many ways of getting around patents, and if they can’t companies still need to sell the stuff to profit here. So the world would get room temperature superconductors if it works.

20 years really isn’t that long and more importantly it doesn’t prevent doing research or building assembly lines or customers designing systems to use the stuff. Nobody could start building assembly lines today, so the difference isn’t even close to the full 20 years here.

If LK-99 pains out they might profit from it for a decade or so while still actually manufacturing the stuff. But, the best case is companies perfecting their process and taking orders so they can start shipping on day 1 after it expires.