Deaths from measles was rare in the US by the time the vaccine became available, due to better nutrition (vitamin A), better antibiotics to treat secondary bacterial pneumonia, and better ICU care. We also have certain populations, like the Amish and Mennonites who tend not to get vaccinated, to which we can compare the vaccinated vs the unvaccinated. There’s no need to wait years for yet another study to be done; the data is already available.

To be the devils advocate, I am sure big pharma would counter that "see how many measles deaths we saved". So to prove the MMR vaccine is worse than the disease it is necessary to estimate how many measles deaths there would have been if MMR was discontinued.

Personally I have only had one flu vaccine and 3 shots of something when I travelled to the south pacific in the last 20 years. I don't plan to get any more shots. I had the measles as a child and survived just fine.