Most semi autos were not designed to feed anything but FMJ (ball) ammunition, which had long been known to have a very poor track record for stopping people. Revolver ammo was not limited to FMJ and even using older designs such as the +P 38 Special 158-grain LSWC-HP ammunition produced much better results in the field.
That in addition to the fact that departments were dealing with institutionalized thinking. Change is incredibly slow. Most people that are in charge of policy change are older and have been in a position or on a department for a long time and suffer from the "Well if it was good enough for me" syndrome and confirmation bias. Look how long it took to get things like night sights or flashlights on handguns. Today there are still a great many agencies that will not allow police officers to have a flashlight on a handgun or a rifle.
I worked for an agency that had a dumbfugg of an uneducated twit in charge of the firearms program that was adamant about never having lights on rifles or handguns. It took me being involved in a shootout in a darkened building where the badguy had knocked out the lights and I was trying to balance a light in one hand and a rifle in the other to cause the department to change.
Consider the liability of trying to take a hostage rescue shot with an iron sighted rifle in the dark, holding it one handed, while balancing a flashlight, hoping you don't shoot the hostage. All because the guy in charge is stuck in the 1980s and has deliberately handicapped you.
Change is slow. Not due to technology, but due to incompetence of those in charge. That is why change is so slow in law enforcement.
Lots of wisdom there.
I saw a few departments with a .357/38 policy for officers so that ammo could be standardized. That was a pretty weak argument in itself.
Some departments said you could carry anything 38spl up... One county I worked in, most departments in it, and most cops in those departments carried N Frames from .41 mag to 45Colt, but the majority in that county carried M29's or 629's.
A few of us carried a 1911 some in the 80's.
