Stating with confidence that anything has been conclusively shown about it is a sign you’re arguing from a position not based on evidence.
There simply is not enough evidence to say anything yet. Claiming there is means you either don’t understand it or are willfully misrepresenting it. Either way: no.
The evidence that has come out so far against LK99 in the past few days is pretty strong (particularly the paper out of Peking), not conclusive but it would take some very strong results in the other direction to suggest we are seeing anything like superconductivity.
I have worked in the field of characterizing high temperature superconductivity, there appears to be a lot of motivated reasoning going on around this topic. I would love for this to pan out and while I was initially skeptical I thought there could be a chance. I think the evidence of the past two days has been pretty strong for the negative case and I have adjusted my likelihoods significantly downwards in response.
I agree that recent results have been negative. The reason why they were negative when other previous ones were more positive is, however, undetermined.
With a process that seems to be highly variable, and that the original paper had a only 1 in 10 chance of any success PLUS one that seems to be highly change to produce similar results (but unconfirmed if the same) I’m not too surprised at the high variability of the tests so far.
Frankly, I think it’ll be several years before we get anything close to more conclusive results in either direction. The replication results so far have been… enthusiastic but not exactly stringently controlled.
There simply is not enough evidence to say anything yet. Claiming there is means you either don’t understand it or are willfully misrepresenting it. Either way: no.