Flu has disappeared worldwide during the Covid pandemic
This should not come as a surprise, and it was largely predictable from the outset.The flu has a base reproduction number (R0) less than 2 (https://www.vdh.virginia.gov/coronavirus/2020/12/07/covid-19...).  Covid has an R0 in the vicinity of 2.5 (https://www.cdc.gov/coronavirus/2019-ncov/hcp/planning-scena...).In the meantime, public health measures like masking and distancing will work against both viruses.  If people become reluctant to socialize because of covid (whether or not there be legal restrictions), they will also not spread the flu.As a broad conclusion, if public health measures reduce the effective reproduction number of Covid to about 1 (stabilizing exponential growth), they will also reduce the effective reproduction number of the flu to something substantially below 1.  Since the flu would have also had a low baseline prevalence in the summer of 2020, it is no wonder that we failed to see a flu season.There's really no need for conspiracy theorizing.