There have been issues with players deliberately griefing things (including by nuking their own posts) even in RPs I've been in, so I won't support it. And then there are the 'I didn't do anything' deleter folks, which became abundant enough for us to have to implement storing of previous post versions.
        Besides, I'd not be happy if a CS I worked hard on, but for some reason forgot to archive, were to be arbitrarily eradicated (besides, people who read back in IC would often still want to see the old characters). 
       Eventually, there would be more convenient way to summon mods, though.