I can suggest several other reasons which don't require the moderators to be actively looking for people to victimise, as you claim:-
3) It would add a not-insignificant extra amount of time to the time that moderators already spend.
4) It isn't necessary when there isn't any content in the posts. Your stated interest is ensuring that no content is lost. If there is no content (and an empty post is as purely content-free as can be), then why bother? It adds to the page-loading time, and wastes space on Max's server.
5) Deletion of spam advertising also adds no content to the Mudcat "knowledge base". If spam is not deleted and spammers find that it stays around, they are more likely to return and flood the forum.
6) The purpose of deletion of flames is to avoid escalation of conflict. As Joe has previously said, deleting something and then quoting what you deleted in the comment would be utterly ridiculous. Should the moderators have to to paraphrase the flames, so you have a long series of moderator comments saying "Martin Gibson flamed catspaw49", "catspaw49 flamed Martin Gibson", etc, etc? This increases the time to load pages, and wastes space on Max's server. I can see no benefit beyond the knowledge that moderators are doing their jobs.
7) Drawing attention to deletion of flames and spams "has little effect as a deterrent to these 'vandals', for it is done with such a fuss as to bring the attention that is so craved by them and is the main reason for their postings", according to a poster called Shambles (thread "BS: Poll - Stop Flaming and Abusive posting", date 30 Aug 04, time 02:33). Silent deletion removes that attention.
8) When a particular poster has been wasting their time for over two years (I didn't realise it was that long - thanks for bringing up that old post to remind us) by repeating the same questions without change, even when answered long ago, then finding further reasons to insult that poster is utterly redundant. And note that insults are *not* anonymous.
9) Knowledge of how much work has been wasted shepherding your obsession may lead to a concerted campaign by the moderators to have you banned permanently.
10) The only "increased division, judgement, restrictions and paranoia" is present with you. No-one else is affected by any of these. If you stopped your campaign, then the restrictions placed on you would stop.