btw, I think it's usually best to assume that there has been a glitch or a mistake, rather than some sort of vindictive / aggressive / undue activity on behalf of Admin or the moderators
Every now and then we do have to start deleting a member's posts, wholesale, but there has usually been a very clear progression before we reach that point, and both the member and the moderators know what is happening, and why. Usually this is a way of keeping an argumentative, spamming or harmful member at bay until Admin can come online and ban the person.
If a post seems to disappear out of the blue, then it has probably disappeared through some sort of error, and a bit of discussion and investigation, and a lot of understanding and kindness, can usually sort it out
All the best,