SheriffNZ:

 

While I think you're correct in that the winter spike isn't as bad as modeled, I also think an element of this is people not reporting positive tests. 

 

But the question is "has  the rate of under reporting changed over time"... the assumption is that its always been underreported 

As mentioned by others the declines in Hospitalisations and waste water tends to indicate that there is a reduction occuring

Whether the  daily number is correct isn't at issue, its whether the reported daily number is less than it was reported a week/month ago,

Which it appears to be..