This is of course easy to say in hindsight, and is absolutely a requirement that should be enforced by the extension appstore, not by individual contributors such as yourself.
[1] Of course, the issue here is that no contracts were signed.
[2] In the specific case I was replying to, there was no malice or intent to hide from you as seller. Yet, a better outcome could have been achieved by advertising the sale to those impacted.
I don't think there is any legal support for what I describe above, but in principle whenever a user signs up for Good Thing, and then gets baitswitched to Evil Thing, the main victim is the user, and it is fair to hold responsible everyone involved in the bait-and-switch maneuver.
At least there's invididual states actually responding to this malpractice: https://pestakeholder.org/reports/2025-state-healthcare-poli...
If the old owner gives their key to the new owner, then they should be on the hook for it. I was thinking of this yesterday, as I think this is also how domains should work.