As long as the use cases are considered properly.
Consider I hit a pet emergency website that is powered by ChatGPT. I ask it what to do because my dog has just had an encounter with a specific poisonous animal. It gives me advice based on a similar, but slightly different situation and my dog dies.
Alternatively say a telecommunications vendor (or for that matter, many SaaS vendors) implement it instead of detailed product docs. It gives me wrong advice and I misconfigure a router. As a result, an emergency call is mis-routed and someone dies.
AI chat isn't even remotely ready for these scenarios yet and there are still plenty of critical infrastructure services that rely on things like email. Therefore even your basic webmail SaaS isn't a suitable target for this type of tech.
Where could you genuinely deploy it safely?