Unfortunately because Discourse can be installed by anyone. It means that not everyone will abide by honorable use & managemrnt.
As @Jagster said though if you’re in places like the EU and the site is in the EU. GDPR laws can be used. You may also have other legal options depending on where you’re located
A lot of the major platforms though be careful as many just take the profile offline from public view vs a delete/anonymization