The problem is this leads to dead forums. Not just the jackass's leaving, but gradually others tend to move somewhere else. Just look at PCpitstop, at one time years ago, it was much like this one, full of various, interesting threads and also some jackass posters here and there.
Then they got strict, within 2 years it went from 20+ threads a day of various topics to just a few that are most all "malware and virus' type stuff from noobies with single digit posts then never return. I left there not because it was the jackass's making the threads...though they sometimes made entertaining ones, but others couldn't really express themselves that much leading to boring posts...i left there, i check in now and then just to chuckle at the lame "i got a virus, check my Highjack logs".
The other posts are made by a few particular people who are Linux obsessed, talk trash about Windows and no one else there knows that much. If you disagree with a subject, often the thread dies as no one responds unless it's political in nature. One particular member there who's like the main one, i can't stand as ever response is pure sarcastic.
So it's a boring forum now. I have come across quite a few like that where i needed specific help and no replies and like 2 views and 2 threads created that week.
Frankly i've noticed most every current member here who posts often has some jackass posts, attacks and other distasteful remarks on occasion.
So no i think you have to let people express themselves #1, otherwise what's the point. Mods can filter out the repeat offenders but you have to have some tolerance, especially in heated debates where responses to posts get taken out of context as if always trying to 1up. A few rule breaks on rare occasion to an otherwise good member 99% of posts should have mild leeway and suspension, not outright ban over 1 particular abuse. I and many others members wouldn't likely be here if it was stricter, but once you remove a bulk of those who post often, you really do end up with a lot of dull reading material for the day until eventually others don't come everyday, then they don't log in but once a week, then a month...etc.