I can't speak to a wide area, but where I live in the US, the flu is definitely not dead. Despite wearing a mask, keeping socially distance and basically not traveling except when essential, I caught type B of the flu, and my doctors told me they've had a shocking number of flu cases.
They seemed to expect to see fewer, too, but have observed the opposite.
That's a good point, my local pharmacist said that sales of cold and cough syrup has been down significantly, almost non existent, since our city has had lockdowns.
They seemed to expect to see fewer, too, but have observed the opposite.