In the age group most at risk of COVID-19 vaccine myocarditis (12–29 years), for every 100 000 vaccinated, compared to about four more cases of myocarditis we have 56 fewer hospitalizations, 13.8 admissions to intensive care and 0.6 fewer deaths. Several studies have shown that post vaccine myocarditis/pericarditis are generally short-lasting phenomena with favourable clinically course.

The paper recognizes a 0.004% increase in mild short term myocarditis, with about a 0.05% decrease in hospitalization, 0.014% decrease in intensive care needs, and a 0.0006% decreased chance of death from COVID.

Of course, all this suggests that in that age range, it's messing with all very low percentages, so it's pretty much a wash whether they vaccinate or not, statistically speaking. But the vaccine risk is not 'much higher' and the severity of the risk is generally low, and seemingly still technically lower risk than COVID itself, but the risk for any of it is kind of down in the noise.