In this preprint, the authors synthesize samples based on the claimed room temperature superconductor LK-99, and observe half-levitation similar to that seen in other recent videos, which has been ascribed to the Meissner Effect (a signature of superconductivity).
However, they performed a careful magnetization measurement and found that the sample is ferromagnetic. They also did a resistance measurement on a larger sample, and found that the majority of the material is a semiconductor. This points to a simpler explanation for the half-levitation phenomenon: it is a consequence of ferromagnetism (+ mechanical effects due to friction and sample shape), rather than the Meissner Effect.
Unless someone can demonstrate full levitation or better resistivity data for LK-99, this is arguably fatal for the claims of room temperature superconductivity.
These are often done purposefully. And the scientists are often repeat offenders of academic fraud. It's a very bad look for their career.
https://www.nature.com/articles/d41586-023-02401-2