pedojacketing
Pedojacketing is a slang term referring to spurious or otherwise not-entirely-honest accusations of pedophilia. The underlying behavior predates the internet, noteworthily having been used historically (not to say that it has stopped being used this way as of 2022) as a method of demonizing gay people. However the term itself is fairly modern, and rose to public consciousness because of how popular aggressively searching for excuses to call someone a pedophile became as a method of getting away with abusing people in public.
I don't think an edgy joke makes someone a pedophile. It might make them cringy and unfunny, but making it out to be more than it is would be pedojacketing.