I once made a reddit comment in anger that was most certainly over the line. I don’t remember the context, but someone had my blood boiling quite badly, which I voiced by wishing pain on them. However, it was a support-oriented community, and my outburst was definitely not tone-appropriate for that environment - the last thing people seeking support need is a graphic description of pain. I got a two-day (I think?) temp ban from that sub, citing that reason. First I was pissed, then reflected, acknowledged my error and didn’t repeat that mistake.

In hindsight, I think that makes for a good moderation approach:

Lock an escalating thread, clean out comments that cross the line, hand out brief temporary bans to particularly excessive offenders or those continuing their venting spree in other threads after the first one was locked, give them an opportunity to step back and reflect.

Of course, there’s still the question of “what do the mods consider excessive?” But that’s a question you’d have either way.