We do not have the data to support or refute the original statement. Mostly because the US has a poor understanding of the uniqueness and context of every person's immune system and how it plays a role in new viruses, reactivating old viruses, depleting nutrition required to successfully fight off multiple strains through the winter season, having multiple pathogens at once and a suppressed immune system, etc. This lack of understanding requires a lot more testing of pathogens, T-cells, mast cells, and signaling (cytokines, etc) from a lot of people. It's usually seen as too costly or invasive. Not that this current pandemic has been costly ;-)

In the US Midwest it was very harsh for flu, conjunctivitis, strep, etc. My children both had coughs, fever, ruptured right ear and one had chicken pox style rash (late December). Doctors never tested my son, my daughter tested negative for flu with multi-day symptoms and then positive for flu A (same test) ~10 days later. So there is/was a definite lack of data. Unfortunately, we do not have the samples to go back in time and apply newer tests. Luckily, France had the foresight to preserve some of the samples.