It's because you need to stop the insane tribalism of one tribe against the other. COVID doesn't care about any tribes. This is not a red and blue issue and it is definitely not about who wore masks and who didn't. California where I live and I suspect many other states that are "red" had private businesses that STILL required masks even if there was a week or so where some governor said businesses could reopen. There was NO time where California's businesses allowed people in stores, etc. without a mask because they were afraid of being sued. Thus, any contention that red states were running around without masks is wrong (South Dakota who has a low death rate excepted).
So, here is what happened and the only logical thing. New York, New Jersey, Conn., and Mass,were literally hammered and everyone there wore masks You know this. The question would be...."Just how many old and sick people were there in those four states that the virus would be able to kill?" and when the virus did that, it was basically done, as we can see from their now very low death rate. Then, we switch to other states, red AND blue that HAD low death rates and we find THEM getting hammered. California is a BLUE state, so you can't single out Texas and cherry pick other red states, as I could do the same and I believe a more careful analysis would show it has zero to do with mask or no mask as we have seen in Sweden, Manaus and Belarus.
So, it is as simple as the states that had a temporary reprieve was just the lull before the storm because there were still victims left for the virus to infect and kill but had not yet gotten around to.