Welcome to the party.
I had the same awakening a few years ago.
The Eli Dicken shooting was a huge eye opener. Eli stopped a shooter in a mall that had an AR, with his Glock CCW, at 40 yards.
I argue from time to time with experts here who think a snub nosed 5 shot j frame is all you need.
Reality isn't a police show from the 80's.
You attacker isn't going to be a stereotyped lone mugger at the ATM.
It will likely be a mass shooter with an AR or a gang of criminals/peaceful protesters with AKs and Glocks with switches.
Predators travel in packs these days.
A 1911 is fine, but you might want to carry spare mags in case of a malfunction, and have a backup ane to exit the area.
These days I carry a SigP365xl with optic and a spare mag. I have 29 rounds on me.
(I would feel comfortable with a 1911 too)
I also have an AR in my truck with 4 30round mags and a few 100 round boxes in the back.
I'm not "taking on" a shooter unless he is shooting at me. I will do the needful if I can, but I won't actively engage. I'm not trained for that, and I'm not a LEO.
The idea is the handgun gets me to the truck, and the rifle gets me home.