Here we go again...
Your statement demonstrates a fundamental misunderstanding of how a dot should be used on a defensive/combat handgun, and the benefits it provides. And law enforcement is NOT using dots to slow cops down. Dots are being used to
improve performance.
The primary benefit of a dot is allowing a
threat focused sight picture... you never focus on the dot, like you would on a front sight and you keep both eyes open. Shooters
are slower when first transitioning because they are still in the habit of bringing their focus back to the gun, looking for the front sight. Once you attain competence with a handgun mounted optic, you will be
faster because you are only looking at the target. The problem is it takes time to break long ingrained habits/skills and the longer you have been shooting, the more time it takes. Many don't have the patience, or fail to put in the time.
As an LE instructor since the 1990s, I've seen a lot of fads come and go. Handgun optics are not one of them. We got serious about the training a few years before I retired. In those few years I taught several hundred LE shooters to use dot sights, both in basic academy and in-service training, and I have personally observed that speed
and accuracy was improved in almost every case.
For anyone interested in why dot sights work, and how they can improve your shooting, I suggest reading Aaron Cowan's white paper on the subject:
http://www.kentuckytacticalofficers.../sage_dynamics_pistol_red_dot_white_paper.pdf