[andai]

I saw a comment here recently with data that showed the rates for myocarditis for both covid and vaccinations respectively, I recall the chance of developing myocarditis after vaccination being 4x lower than after getting covid.

Assuming that's right (perhaps someone more knowledgeable can provide a source), this seems to imply that vaccination reduces the risk of developing myocarditis by 4x, assuming everyone will eventually be infected.

I'm also curious what effect age has on the risk in both cases, ie. if the same ratio holds for young people.

[rossnordby]

I believe that is correct. I don't have a great source handy, but here's a preprint which agrees:

Conclusions: Myocarditis (or pericarditis or myopericarditis) from primary COVID19 infection occurred at a rate as high as 450 per million in young males. Young males infected with the virus are up 6 times more likely to develop myocarditis as those who have received the vaccine.

https://pubmed.ncbi.nlm.nih.gov/34341797/

Not sure about ratio age dependency. My prior would be that it is similar, since I don't have any reason to suspect otherwise. Still not a doctor or biologist though :P