We have the same experience. The most members use blogs as a kind of personal forum to ask questions. When they get enough answers, they remove the entry or hide it. Those who have commented are insulted. We would not like to remove the permissions to delete, edit or moderate own blogs. But the most users abuse these features. We have tried to put rules on the entry submission screen, this does not help. We have tried to explain, what blogging is, it did not help as well.
At the end of the day, we will close our blogs after 15 years. We have over 10,000 “blog” entries. The most of them are just questions, 1–2 lines.
I think, there is no IPS's “fault”. We have just a wrong target audience.