I am getting a distance of 180-185 from my 7 iron. I think you just need to hit on an accurate monitor in a constant condition to see how far you hit them. You may be just mishitting your clubs causing your distance to be shorter.

References published by Trackman would indicate a 90mph swing speed is PGA tour caliber and their carry distance is on average 172 yards. I don't swing a 7 iron quite that fast so I carry my 7 iron 168 yards. I would be less concerned with your raw distance and more concerned with your yardage gaps. Ideally you would have about a 12 yard gap in all of your irons. If you were hitting your 8 iron 150-155 yards I don't think you want your 7 iron to carry more than 165-168. One thing that does come to mind is that for the 716 cb irons the longer irons have tungsten weighting to lower center of gravity and increase MOI while the shorter irons do not. I don't recall exactly where that change occurs in the set (maybe the 7 iron). In any event if you feel something is wrong I think your first step needs to be getting your loft and lie checked on your irons. I don't know how long you've had those irons but they're forged and especially if you've been hitting off mats in the winter the loft/lie could have been impacted. Then I would say you need to get yourself on a launch monitor and get yourself a good baseline for how far you carry each of your irons. I know Trackman also has a shot optimizer for driver, I don't recall if the same feature exists for irons but that will allow you to look at how other variables such as spin, launch angle, etc. impact your distances. It's possible you're hitting your 7 iron with too much spin and the ball is "ballooning". You may also want to work with a fitter who could help address these problems and propose a solution. Again though the greatest concern should be the yardage gaps and knowing how far each of your irons carry.

Best of luck!

Did you get fit into the CBs?

Check the lofts and lie angles.

Check the your trajectory! I think you either miss hit or make too much loft on your apex.