No, a quick call is not a courteous first step when someone tells you that you've destroyed 20 years of their work and they no longer want to have anything to do with you.
Suggesting that such an offence can be resolved by a "quick call" is extraordinarily disrespectful. A courteous first step would have been to apologise profusely, revert the damage that the bot did, and ask to set up a call to discuss what it might take to re-enable it in the future.
This is NOT the leader of the new transition tool! This is just a customer service manager in Indonesia who is trying to gather more information.
The steps that you describe might well be taken after the "quick call" gathers more information and figures out the people to escalate it to.
You are being entirely unreasonable in what you are demanding. This isn't a response from the Mozilla CEO. This is sometime in customer service, responding to a short post in a forum. Their response is entirely appropriate as a first step.
If she doesn't have responsibility for this, she just shouldn't respond. The transition team should have responded. Or, she could have responded with "I'm contacting the transition team leader to escalate your issues as soon as possible" or similar. There is absolutely no excuse for responding to someone who has announced that they are quitting over very explicit grievances with "let's hop on a call to get some details". If ever there is a time to escalate, it is this.
To escalate, you need to have a better idea of the issues to know who to escalate to. Plus this is turning into a personal issue (quitting) so a forum isn't appropriate for that part. Asking to talk on the phone is a perfectly reasonable, appropriate, and sensitive way to find out more and figure out how to most helpfully address things. A phone call is the first step in escalation. I honestly don't understand your negative read here. Things don't get 100% addressed immediately in a single exchange. Communication is a back and forth process and this is an entirely appropriate initial response from a customer service manager.
Suggesting that such an offence can be resolved by a "quick call" is extraordinarily disrespectful. A courteous first step would have been to apologise profusely, revert the damage that the bot did, and ask to set up a call to discuss what it might take to re-enable it in the future.