If you want to say COVID and myocarditis are equally bad, you should compare the rates of both of them. You are saying myocarditis (often mild) should be compared to COVID (but only the cases that require hospitalization.)

By that logic, my investment strategy of invest in index funds (goes up over time) is inferior to yours of invest in lottery tickets (but we only consider tickets that won.)

So wouldn't the correct comparison be comparing hospitalizations due to CAE to hospitalizations due to covid?

Another important thing to ask is the risk of myocarditis due to covid, vs the risk of myocarditis due to the vaccine.