Nothing wrong with a shotgun for home defense. Just use appropriate ammo. Not knocking anyone who chooses a rifle or handgun for home defense either. However IMHO it is hard to beat the simplicity of use of a quality pump gun. Especially if you are woke up in the middle of the night and have to instantly take action to protect yourself and loved ones. Yes in large part a shotgun is pointed not aimed but still requires some practice to do it right.
To secure the home I believe a shotgun is every bit as good of a tool as any other gun can be
Why a pump shotgun? I have an older 73 year old friend who was basically a mentor to me at my job and he is now retired. He is scared due to the riots etc. He asked me what type of gun he should buy for self protection at his condo. Of course people tell him to buy a 45 or an AR and some gun counter salesman told him to buy a pump shotgun. I said NO, what you need is a lightweight semi-auto shotgun. I told him as a senior he might have trouble pumping a shotgun when the nerves kick in and the SHTF. I also told him arthritis and old age may make him pump the shotgun too slow. I'm going to help him select a shorter barrel semi-auto shotgun and get a tactical light on it. He can load it and put it on safe under his bed (he has no grandchildren / no little kids around). Then if the SHTF all he has to do is grab it and flip it off safe and point it and shoot if needed. Plus if he got wounded in the arm he could still cycle the loaded semi-auto shotgun. I feel that in self defense situations for many people it's better to go semi-auto instead of pump shotgun.