This is obnoxious. You cannot disprove a scientific study by pointing at who funded it, and a properly constructed one won't be able to hide bad results since it'd be preregistered.
He doesn't have the burden of disproving it, the study has the burden of proving its claims. I consider studies funded by an interested party as weak evidence at best - perhaps enough to encourage an independent party to conduct another study.
All medicines in the US are approved using studies funded by the company that submitted them. There's a simple reason for that - nobody else would care enough to do it.
If you can't read a study well enough to tell if the methods it uses are good, that's your problem.
Proving or disproving a claim is the purpose of a study. At this point, it's out of the researchers hands and up to other research teams to replicate the research and confirm or deny the results.
It's not an effective heuristic. Overly online cynical people are just obsessed with the idea that everything is a conspiracy that can be undone by "following the money".
Bad science reporting is common, but it's more common for the reporters to just misread what a study says.
