Per your post...you're accusing the CDC of "decreasing" the number of breakthrough infections...
"But NOW, and only for fully vaccinated people, the CDC will only accept samples achieved from 28 cycles or fewer. That can only be a deliberate decision in order to decrease the number of “breakthrough infections” being officially recorded."
However, the data being publicized here in the U.S. and in Israel shows "Increasing" breakthrough infections...and a consequent decrease in efficacy of the vaccines due to the Delta variant. If they take Ct's in the range of 35-40...they'll likely get even more positive cases.
I'm not sure what you're getting at.