Thanks for looking into it @codinghorror
I respect that spam magnets are a thing, though every forum topic is a candidate these days. Even this one, that has been open for a while - an accidental ghost bump would lead to community confusion depending how familiar you are with Discourse moderation.
Mods are going to do what they do best either way - they see the topic title when handling spam and can close the topic if they feel it would be a benefit.
By auto fixing bump date if the last post was spam will cut mod work in half, and lead to better category list experiences (there are a few) for the broader community.
Your workflow is solid (separate tasks); though I’m certain you too would appreciate less clicks / page loads if given the choice, especially against bots 