I feel is the ban is good and should be permanent because we have to remember that ChatGPT is really just a more interactive search engine and its results, whilst clever, are still the result of scraping existing web pages - just like any other search engine.
By allowing ChatGPT answers on SOStack Overflow (and other sites), we'd be creating an echo chamber whereby the answers it generates are simply based on its previous answers, which may not have been right in the first place.