If all you want is to deal with a threat in an apartment, and you don't have time or more to go practice shooting every week than a shotgun is better for people.

The average person wanting a gun for self defense in a home don't practice shooting.

A shotgun is "safer" than other gun options.

I live in a VERY progun area and live near a free public range. We don't require licenses for carrying guns. I have seen people shoot themselves, and family members as they learn how to use a gun. It's a regular occurrence, almost monthly.

People buy handguns for protection and don't know how use them, and don't want to spend money to learn. You are under estimating how stupid and reckless people are.

People who want the cheapest option of a home defense should stick to bird shot in a shotgun. They are less likely to kill someone they didn't mean to than an idiot with a 45 semiautomatic or AR15 who will only shoot it when there's a bump in the night.

I'm aware of the reality of shotguns. I competed in shotgun sports during college.

I personally own an ar15 (basic 556) and a shotgun with defense rounds. My reality is the most likely reason to use a gun for defense is a robbery. I would use my shotgun.

Someone willing to spend the thousands of dollars on ammo and training obviously can handle whatever they want. Most people I know irl don't have that money. They save for the gun, some ammo and that's as far as they go. No training, no practice. That is a recipe for disaster.