This was the key figure in a Nature Medicine paper published on Dec 14, 2021. It showed clearly that myocarditis after vaccination (in this case, Moderna dose 2) was higher! than myocarditis after sars-cov-2 infection for people <40.
There were a few remaining issues. While the denominator for vaccines is known with precision, the true number of infections is unknown. Many people don’t seek testing or medical care. So the red bar above will be shorter if you used a sero-prevalence (aka the correct) denominator. The authors needed to fix this.
The other problem is that this analysis lumps together men & women, while men have the greatest risk. Well, the authors are back with a new pre-print to fix this point, and here is what they find.
It is now clear for men <40, dose 2 and dose 3 of Pfizer have more myocarditis than sars-cov-2 infection, and this is true for dose 1 and dose 2 of Moderna.