This is really more of a question you should answer per situation.
In situations where you're in a small apartment that doesn't have enough room for the shot to properly spread out a shotgun is just going to be unwieldy and not be used to its full potential. For anons with small homes I'd recommend that sweet AR pistol in .300blk with a 10" barrel.
Why?
Well I'll tell you anon.
Shotgun shot needs distance to spread out and be effective around 15-20 yards which most of you have less distance than that between your front door and your room.
>https://rifleshooter.com/2013/01/defensive-shotgun-patterning-deconstructing-the-1-per-yard-myth/Otherwise you're just blasting large holes in the intruder and potentially you home. As well a shotgun is typically long unless you have alphabet boy stamps and has a low round count ranging anywhere from 5-7 rounds. A shotgun as well has more felt recoil meaning that if you don't land with the first shot the enemy might have time to return fire. Follow up shots will be critical.
A pistol, PCC or any SBR is going to be infinitely better than a shotgun for HD especially in a looter scenario since overpenetration is not a factor. We could get into how it takes longer to reload a shotgun and that you want maximum rounds on target in case of an extended firefight but that just opens the door for
>hurr durr get a load of this operatorSo we'll just leave it at that.
tl;dr: shotguns are shit for home defense and only fudds believe in shotguns and .45ACP