As a former mod, I understand why some mods used automatic bans. I modded a few moderate sized subs and noticed posting trends in other subs amongst troublemakers. "For some reason", many active posters in r/TheDonald, r/Conservative, and similar subs were far more likely to be offensive or hurtful and didn't have much that was interesting, helpful, or constructive to say. Certainly nothing valuable enough to tolerate their shit. When we'd temporarily block one of them for name calling or other personal attacks, we'd get messages ad nauseam claiming we had violated their first amendment rights, that they were going to find and harm us in some way, or just a bunch of further name calling and personal attacks. I had two try to dox me. Poorly. They weren't very bright.
With that being said, we didn't use auto bans because they're chickenshit. Yeah, they would save us a fair amount of time and aggravation, but they'd also ban people like you and me, who may have told some Nazis to fuck off or explained, line by line, how the latest thing Joe Rogan or Bench Appearo shit out their mouth was exactly that: shit. If you're going to mod a community, it's kind of what you sign up for. If you can't handle it, then quit or get more backup. Don't ruin it for others because you can't or don't want to deal with the unpleasant aspects of the job.