I will try to explain as much as I have been able to research the issue.

The flu is still being passed around but not as much as in previous years. It seems people walk around with asymptomatic flu for about a day where they can spread the virus before becoming ill and then recovering at home.

With the SARS-Cov-2 virus, people can walk around asymptoatic for several days and spread it before becoming ill and then recovering at home. That 7-14 day gap of asymptomatic transmission seems to be the key here vs a lower gap of asymptomatic transmision for the various flu viruses.

So the lock downs from the 2020-2021 season seem to have caused the flue to not spread as rapidly (while SARS-Cov-2 can still spread rapidly from the asymptomatic transmission).

the 2021-2022 season has only just begun so there is not much data yet. Here in the U.S., the CDC tracks it by state here:

[link to www.cdc.gov (secure)]

based on the map near the end of that page, where you can switch between the current season and prior seasons, you can see that the current week ending 46 (november 20th) is showing more activity for influenza than week ending 46 from the prior season. This could be due to people returning to public places and going out more often instead of being locked down, so the flu appears to be coming back now.