I disagree, first party tends to have a large advantage in combatting spam, because first party can fingerprint users with a wide variety of methods ranging from IP, login information, user behavior, registration dates, etc.
You can use word filters to create triggers on users, and moderators/staff/admins to create rules about what is bad behavior and issue timeouts/bans automatically.
Third parties don’t have the fingerprinting data, so they can only use a subset of available information to create rules to catch bad behavior.