Locking the trigger, keeping the gun unloaded with the trigger lock engaged is exactly the same as not having a self-defense gun in the first place.
The over 2,000,000 incidents a year reported by the FBI of cases where a self-defense gun was used to deter or prevent crime is testimony that the average person knows more about safe firearm storage than they are given credit for.
Rather these people, who are out of their field, should be giving advise on safe ways to protect children. One of the best ways is a handy 12-guage sawed-off pump.
Back when I was single, living by myself and into it, I kept it next to my bed where it I could get to it if required. Then I met my wife, and like so many other men, found that I didn't have the time to stay proficient with it and could not get my wife interested in anything to do with firearms. Once the kids came along, it had to kept out of reach when they were little. Now my boy is 7 and can get to almost anyplace in the house if he knows there is something he wants to get to. Currently he doesn't know that I even have firearms, and if he happens to discover them, the trigger locks will at least stop him from pulling the trigger (they are unloaded). My guns are presently nothing more to me than sports equipment that don't get used anymore, and when I find a buyer who will pay a fair price, I will probably sell them, unless in the meantime a civil war starts here............