It's reasonable to expect more frequent trips to the NCAA than we had pre-Hoiberg. It's also not reasonable to expect getting into the tournament for streaks of 6 consecutive years like ISU did in by far its best period of sustained success.
Personally I will never be mad about and ISU team getting a 4, 5 or 6 seed like ISU has since Prohm took over. Could it have been better, sure? But I don't agree with those calling any of those teams failures or major underachievers. Last years team had significant roster turnover and uncertainty not all that different to those in 2011-12 and 12-13. Those teams were 8 and 10 seeds. You can argue which of these rosters had more turnover, more talent, etc., but those differences are not so glaring that you can with certainty call an 8 or 10 seed a success and a 6 seed a failure. It's easy to be really excited about an 8 or 10 seed when you are coming off a six year post season drought. It's tougher to get excited about a wildly inconsistent 6 seed when you are coming off of a recently ended 6 year NCAA streak.
With that said, I just don't see how this years team can be this bad. Not make the tournament, that's one thing. But they are SO bad and just not even competitive in so many games.