You don't have to delete everything. In case of ranking lists, it would sufficient to tombstone the data; replace the name with "[deleted account]" and link it

You don't have to delete everything. In case of ranking lists, it would sufficient to tombstone the data; replace the name with "[deleted account]" and link it to a page that explains the account data was requested to be deleted. GDPR Deletion Requests only cover data for which's processing you either used consent, used the legitimate interest clause or is part of a protected category (sexuality, religion, etc.). Some parts of "legitimate interest" that continue to be legitimate interest (like for example, billing information for tax and fraud prevention) you may continue to keep it around as well.