I think the amount of money is explained in part by hubris. People in high positions think they're at least what they earn more smart and capable than people at the bottom of the org. So its reasonable, expected, borderline obvious that a computer bot can replace that person. So you're betting on the ability of it to get rid, if not of your junior devs at least the majority of your customer support staff.

In reality people doing "menial" jobs are smart and learn and operate with a lot of nuance than people ignore given unfamiliarity or just prejudice. Do you prefer to talk to a chatbot or a real human when you have a problem, how confident are you really, that even if the bot knows what the problem is it would be able to solve it.

Lots of problems with customer care is anchored in the issue that support staff is not allowed to fix or resolve problems without escalation or attempts at keeping you from costing more money. The bot might be better at it for the company because it will frustrate you enough to give up that 30 bucks refund, idk.

Ai seems to change a lot the dynamics of corporate jobs but I haven't seen yet anything that would be a game changer outside of it. Its great for searching company unorganised and messy knowledge bases.