Regardless of what some may have you believe, you are in a lot more danger from the bad guys on the street who can and will do serious harm to you if you can’t defend yourself efficiently than you are from your own sidearm, especially if you are well trained in its use.
There are those who will argue that it doesn’t take any extra time for a proficient officer to engage a lethal threat with a firearm that has a manual safety (such as a 1911 design or a Beretta 92 carried with the safety engaged). While this may be true, it is certainly not true that most trained officers can return those firearms to their safe mode as quickly as they could return a firearm without such a device to its safe mode.
The reason should be obvious: double-action/single-action and single-action-only pistols are designed to be in their double action or on safe mode, respectively, when they are not actively being shot. To engage in any other activity with these guns in single action is potentially more dangerous because the firearm is in a condition where the trigger travel is short and the pressure needed to engage it is light.
So even if we take away the “from the holster” delay/distraction that these guns can and do suffer from, we run pretty squarely into a more complicated situation if after a shooting, or deciding not to take a shot, the officer needs to do anything else, including re-holstering quickly and safely to deal with the aftermath of a shooting incident.
The “safe-action” type striker-fired and double-action-only pistols do not suffer from either the extra physical action at deployment or the added cognitive and physical necessities after a shooting to be used effectively.