Spammers don't care. I've seen some accounts which can churn out a post a minute by just picking up on a key word or two in the topic's title/subject and churning out the most generic one liner. Even if half of their posts get reported and deleted, they can still max out the requirements for their bounty campaign in under an hour. And if all their posts get trashed, no worries, they can come back and do the same thing tomorrow. Beyond seven days they don't care if their posts get trashed - they've already been paid. They don't care if their posts are overlooked, and they don't care if they end up on ignore lists - there is no way to track this, so they will still get paid their worthless tokens. And in the case of thread bumping, they again don't care if their post is overlooked, reported, deleted, they are ignored, banned, or so forth. As long as the thread gets bumped, they get their payment.

Spam isn't a problem you can solve by presenting reason and logic. As long as there are ICOs and similar scam projects willing to pay for spamming and bumping, it will continue to happen.