One can try to rationally argue their way out of alcoholism being a moral failing, but then one notices that in a similar way they can “whitewash” any other moral failing, and the words lose their meaning completely.
Yet people use these words to mean something, and abuse of alcohol falls under that meaning, and every society in existence has always cautioned against and condemned it.
It doesn't. If thievery is a moral failing, how can chopping off thief's hands resolve it? It does resolve further thievery, but doesn't resolve the moral failing of it.
But we may be using different definitions of moral failing
If it just cures the bad habit without the mental work, then probably it would be more appropriate to view it as a remedy for a disease rather than a temporary band-aid for people who are unwilling to put in the work.