All you mentioned are important factors in determining or concealing the real numbers.
Trump is doing none of that.
I am thoroughly unconvinced.
There is a reason that Worldometer's numbers of dead for the US are lower than the CDC's numbers.
We also know multiple states have stopped being as forthcoming with their number, following some of Trump's comments - all with GOP governors.
Trump may not be causing folks to mess with the numbers, but I see no reason to be sure of it.