Based on the data in your first paragraph (the first article linked), it appears that the risk of COVID-caused myocarditis is about 13x greater than the risk of vaccine-caused myocarditis (0.1000% / 0.0076%).
The problem with this myocarditis comparison is that it appears to not take into account the overall risk of being infected with COVID.
In order to compare apples to apples, we have to revise the 0.1% risk of COVID-caused myocarditis by factoring in the overall risk of being infected with COVID at all.
If the risk of contracting COVID is less than 1 in 13, then the myocarditis risk is a wash.
(*** My guess is that the risk of contracting COVID is much higher than 7.7%, which means that COVID-caused myocarditis is still much more likely than vaccine-caused myocarditis.)
One thing not discussed in all of this is whether or not the risk of COVID-caused myocarditis is decreased in vaccinated individuals. This matter a lot because the data indicates that vaccination—while very effective at decreasing the severity of symptoms—doesn’t do much to lower the overall risk of infection.