That's not the way the burden of proof goes! Consider "Fluoride Toothpaste is not a Superconductor".
What you want is conspiracy logic: assume something interesting is probably true based on weak evidence (a handful of videos on twitter seems like table stakes in this particular controversy), and then when people deny it you demand that it "should directly reference strong evidence".
No, the reality is we're not getting reproductions. You're doing the same thing the upthread poster is and demanding that in the absence of evidence, we believe the most interesting assertion. But no, that's not how it works, and that's what the tweet is trying to tell you. It only seems "tone deaf" if you're invested in the argument.
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.