Myocarditis can be caused by viruses too. The chances of getting myocarditis from COVID are sixteen times greater than from the vaccine.
The study you quoted does not say what you say it does. Here is what is being compared, from the study. It compares risk for patients with and without COVID-19, not those vaccinated.
The risk for myocarditis among patients with COVID-19 during March 2020–January 2021 was nearly 16 times as high as the risk among patients without COVID-19
It says a patient with COVID-19 is 16 times more likely to have myocarditis, compared to a patient without COVID-9. It makes no comparison whatsoever to the risk of getting myocarditis from the vacine.
If we know how many people, in which age categories get myocarditis after being vacinated, then we can evaluate the risk compared to the elevated risk of myocarditis from COVID-19. At present, the percentage appears unknown.
People have gotten Myocarditis from the flu and the flu vaccine for years. This is nothing new. But none of my friends have died from the shot but I lost 2 friends in the last 30 days from Covid. One vaxxed, one not.