I think most people watching that clip wouldn't ascribe malice to him, but it does demonstrate why the man was an incredibly Dangerous person to have as president.

Maybe he thought a sarcastic reference to ingesting disinfectant would liven up his advanced knowledge of obscure experimental UV therapies?

I'm going with the alternate hypothesis that he was an layman with a very limited grasp of what he'd been told would kill the virus fumbling around trying to find reasons for the public to believe that a cure was imminent. That is sort of his job, and whilst I think most politicians would convey such messages less ineptly, to be honest I have less issue with Trump in this particular instance than the people who actually ingested bleach to own the libs, or continued to insist even after Trump himself had walked back the remarks by claiming they were [very inappropriate] sarcasm that Trump was passing on advanced medical knowledge and the only problem with those remarks was that the media and medical didn't appreciate them enough.