I believe they need to collect data on the iron sights, so they are forcing everyone to use it. If they told you use camera mode or iron sights mode, barely any one would use the iron sights.
I believe they should have these types of sights.

Ironsight-Close Quarters. No CPU usage and no Isk.
Effective for cqc. //Mildly effective for short range combat. //Ineffective for long range.

Red Dot (Or Green/Blue/ What ever really) Close Quarters to Short Range. Mild CPU usage and Isk
Effective for close range // Mildly effective for medium ranged combat//and ineffective for long range.

2x Scope- Short to Midrange. Average CPU usage and Isk.
Mildly effective for close range //Effective for medium ranged to skirmishGÇÖs,// and mildly effective for long range.

4x Scope-Midrange to Long range. Increased CPU usage and Isk.
Ineffective for cqc.//Effective for midrange.//Effective for long-range.

Of course and further balancing to prevent the gun from becoming mini sniper rifles.

I would like to see some advanced optics as well, such as NV, IR, or even some futuretech gravimetric imager that can see through walls. Make it expensive of course.