This is what I told them:
Either way I really, really, really, really, really think this is an absolutely terrible idea to do.
Even anonymized, if this data got into the wrong hands, the black hat community could royally fuck your whole company sideways based on reverse
In the past week there have been 2+ companies running around offering $200K - $2M for "anonymized Slack, email, and business workflow data (to resell as AI training data)
This founder followed up saying they got offered $1M for a team of 50-100 employees (trying to make this

