A minimum post count is better than unlimited. Minimum post counts usually aren't excessive so the user isn't forced to make hundreds, but a user has to make a minimum of x amount posts otherwise people just won't do anything. A better solution would be to actually make managers do something about spam. When you have managers like sylon who accept hundreds of users and don't do any sort of quality checks then that's when they get abused. Chipmixer has a minimum requirement of 50 posts a week but we don't see any spam coming from their campaign. The onus should be on poor managers not what minimum amount of posts are required because any amount of posts will include spam if nobody is poling them.