Flu isn’t as transmissible as Covid. The UNPRECEDENTED GLOBAL COUNTERMEASURES we have taken against Covid have been doubly effective against the less transmissible virus. The masks, the social distancing, the self quarantining at the first sign of illness, the decreased congregating, decreased inter and intranational travel, the mandatory flu vaccines, etc, etc, etc have all stopped influenza dead in its tracks. And that’s a good thing. It’s exactly what we wanted. We did not want to be battling both of these bugs at the same time.
If anything, the mask wearing made it worse.
Add to that, people think that hand sanitizers are a substitute for washing.
Then there is the respiratory distress from people wearing non clean mask, ie wearing same mask for days or weeks, careless handling of mask and other non sanitary habits of mask wearing.