> In order to preserve the usefulness of those models and the hundreds of millions in R&D spent to develop them, you have to carefully understand exactly what products and algos will be affected by just deleting a single record.
Exactly. The ability to delete user data should have been something engineered from the ground up. They are paying the penalty of technical debt and hopefully learning some tough lessons.
My answer to that is 'who cares?'
It's not my problem, let me delete all my data.
In fact it's required by law in some places.