I think chatbots are mostly used as one more speedbump in getting to an actual human for customer service.
The are the equivalent of "music on hold" when you're dealing with a website. The chatboxt asks a lot of questions to slow you down and discourage all but the most persistent customer.
On most sites the chatbox requires you to enter your customer information -- stuff like name, customer id, order number, etc. and then like the phone real world when you do get connected to an agent, none of that information pops on screen so they have to ask you the same info again.
And like the real world, your chances of getting disconnected while waiting for an agent are really high.
The physical equivalent would be a really long queue where you have to fill out many forms and randomly someone comes and kicks you out of line. If you ever do get to the front, the agent throws your forms in the trash.
There is no effort put into good chat bots... they are just designed to slow the "because of unusually high demand your wait time may be .... forever".