You are certainly correct that Trump didn't refer directly to COVID as a hoax, but only in the literal sense and especially when given the chance in the following days to clean it up. However, applying literalism to Trump's words or even divining a context is a fool's errand. He so often seemed to be talking directly to his 'fifth avenue', ride-or-die supporters, hungry to depict him as a victim of the treachery of an 'angry', 'elitist', liberal Left.

One time he failed to clean it up was the very famous time he referred to getting disinfectant into the body as a COVID remedy, although he never literally said the oft-repeated phrase 'inject bleach'. After doctors were left condemning his comments, he said that he was being sarcastic, which I think is non-sensical given the subject matter (i.e., in the middle of the a pandemic, during a press conference surrounded by doctors, POTUS wants to go spit-balling on potential remedies and get all sarcastic on... disinfectants & their applicability to this virus).

As far as presidential responsibility for COVID deaths go, I think things are a bit different now owing to personal responsibility. Since we have vaccines now, should you refuse the vaccine and then die from the virus can you really blame POTUS for your death? Biden took the unusual step of reneging on his promise against vaccine mandates to do just that later once there was a new wave of deaths in August 2021. I give him credit for casting aside the obvious political implications of reneging on a promise and that of a obviously unpopular mandate, as well. To then blame this same POTUS for more deaths seems especially unfair. Biden and his medical advisors know the truth that this virus just won't 'go away' as Trump would like to say with a flick of his wrist in its early days, and that we will have to get bare-knuckled about it or suffer more deaths from evermore mutations.