You are both misreading the data. Hundreds of thousands die from the flu because millions contracted it. Only a few hundred contracted the measles in comparison. This isn’t “hysteria”. Peoples lives are in danger because people like you think its OK if some people choose to allow their children to acquire dangerous diseases. Look at what happened in Eretz Yisroel last week, R”L. Nearly 30 newborns were in potential danger of death because a mother with measles gave birth in the maternity ward!
If you are honest with yourselves, you would look at the data comparing hospitilization and injury rates for people already diagnosed with measles or flu. (Hint: the data shows that measles is far far worse)