I think you number is low, really low. COVID didn't really gain traction until April, only 4 months ago. The infection rate is increasing every day. We face 5 very long months, with a virus that has a lot of traction.
Any day in July has significantly more infections than even June, and a whole more than May. This is not just because of testing, as the hospitalizations and body count attest.
I fear we will be in the 400 - 500K by year end. By the time we are ready to put COVID into the history books, I fear my 1,000,000+ guess is still valid, all on Trump through his gross incompetence and indifference owns it.
my take is there is no way to know the really # until couple yrs down the road when we compare the norm to 2020/21, the "official" number are off and no one knows how by how much. Any by that I don't mean just USA it apply to all countries. And to your prediction I don't think it will get that high(I sure hope not), the more we know about the virus the lower death # we will get.