No, it's mostly the lag in death certificates coming in. This is the raw number of death certificates filed. Column 4 shows the deaths certificates recorded in the 7/3 to 7/9 period for the different weeks ending. For example, 38 more death certificates were filed for the week ending 2/1/2020 (!) during the period of 7/3 to 7/10. This is raw CDC data in columns 1-4 and the rest is manipulated as shown.
The improvement in estimated excess deaths is probably better treatments and the average age of cases being 15 years younger and maybe the new strain (European) being less virulent. Unfortunately, too many independent variables for me to know.
View attachment 8546
And yes the number of extrapolated excess deaths is falling off through the week ending 7/4/2020. We'll see how long that continues with cases and hospital intakes up.