Oh it could have gone worse, but for that to happen you needed a harder drug than crack or as hard a drug. By which I mean, dirt cheap to make and with low street price, high addiction rate and an upper. My best pal went to high school right after the crack epidemic was dying down, though things were still dangerous, in Jordan High School (which is not in Watts, because it is deliberately just on the outside of Watts so people running it can say it's not in Watts) and as he eloquently put it, "Nobody wants to get killed over weed, man."
As how bad it could have gotten? Parts of the city would have been no-go areas to present day. But please note I said parts. That's the one thing about failed states and horrible towns, even in the middle of all the chaos, there are 'safe' spots where police are concentrated and people of privilege are allowed to live their lives as if nothing is happening. Even during the height of the crack years, most of Los Angeles was actually safe, provided you were white and not poor.