IMHO threads are either serious or entertainment. Self moderated threads, for me, automatically fall in the latter because why would you waste time posting anything serious in a discussion where the other guy can just delete you if they don't like it.
Maybe you haven't created any topics on this forum lately - if you don't get ad-sigged to death then you'll get trolled to death or whatever.
Freedom of speech should not mean "freedom to take a dump wherever I want to".
Unfortunately these days many people seem to think that taking a dump is exactly what they should do (of course they'd never dare to do such a thing IRL but there you have it).
You can always create a new thread that is not self-moderated - so why get upset by one that is?
Most of those who are long-standing forum members who actually care about communicating do use self-moderated topics now as we have ended up with no other choice (unless you want your topic to quickly become a complete mess of ad-sig rubbish posts and trolls).