I think part of the problem with reporting posts and getting them deleted is that it isn't really a punishment. A spammer can easily churn out a one line shitpost in under a minute. Even if 50% of their posts are getting deleted, they can still max out their bounty campaign easily enough.

How would people feel about some form of punishment? If you had 10 posts deleted in a week (for example), you are either banned or lose your signature for a week, with escalating punishments for repeat offenders.

Knowing there is a punishment might serve to get more people reporting, as well as serving as education for the spammers who are currently having their posts deleted and retaliating simply by posting more.