The wrench in that natural balance is that the vaccinated create artificial variations in the population-wide level of "fuel" available for the virus to burn, so they can keep adding fuel and prolong the waves, as seems to be happening in the UK. However, as noted in my Friday post, the southern US magically escaped this fate, so maybe that's not really at play at all.

In natural conditions "lack of a wave" should be accompanied by a slow drift to higher population-wide potency and "wave" should be accompanied by a rapid reversal to not-potency. "Seasonality" is plausibly just the synchronization of that continual drift with exogenous changes to potency, i.e. weather and behavior, etc.