Not the same person here, but a data point nonetheless. Before supplementing D3 I had a cold basically every year, sometimes twice a year. Since I brushed up my levels I average 1 cold in 6 years.
Oddly, since the Covid time, I haven't caught a cold or flu once. I'm not sure it's the vaccines, the flu shots, or the less physical contacts on things overall. I still go to crowded places from time to time, like plane or train rides. May be the population in general have less cold or flu virus overall to go around.