You're free to speculate that Meta is lying about what it will or won't use the data for. I won't argue over that. That's an important topic and I'm not gonna persuade anyone via an HN comment. Skepticism is fine
But the example linked to in the above comment is not evidence of that at all. A skill explaining how to format purchase history in markdown format is not evidence of hidden motivations.
In general the entire thread is nothing-burger, and that's all I'm getting at.