The president will be held responsible in comparison to best practices. To the extent New Zealand, Australia, Japan, South Korea, Germany had infection, death, job loss and economic contraction, we can attribute that to the virus. To the extent that any of that was worse in the US, we can attribute to the White House. The White House will be accountable to the extent the poor results are attributable to the mismanagement of the response to the crisis. And, there most certainly was mismanagement. Those comparisons will be made and turned into 30 and 60 second spots, that will be damning.
But in the end, to quote James Carville, "its the economy, stupid". If we are still reeling in November, and we will be, those effected by all of this (out of a job or missing a loved one) will not be voting for Trump.