peterdsharpe parent
There is a difference between saying "We believe LK-99 is NOT a superconductor" and "We do not believe LK-99 is a superconductor". The former is a hypothesis, the latter is a rejection of a hypothesis. The latter is really just expressing a return to an agnostic base state. Hence, the former requires evidence, and the latter is the null hypothesis.
The grandparent was demanding data and evidence to argue about the status of superconduction in a real material. What you wrote is just a semantic argument.[1]
And you're right. But you're not telling us anything about LK-99. If you want to tell me that the linked tweet is a little hyperbolic and could be stated more rigorously, I'd agree! But we both know that's not the frame of the comment I was responding to. The upthread posters "wants to believe", and is looking for reasons to reject the tweet's opinion, not its language.
[1] Which, notably, ignored my toothpaste analogy.