That's not what the GP said. They said Huberman's incorrect statements on something they understood made them more skeptical regarding his other statements, not that these other statements were definitely wrong because the first statements were wrong. It's about judging Huberman's reliability as a source of information, not deciding whether he's correct or not, ie whether it makes sense to take Huberman at his word or whether one should doublecheck the things that he says.

Sure, but if he has a track record of being wrong about X then being skeptical of future claims seems reasonable.