I just cancelled my ACF subscription as it's up for renewal in 30 days. I'll wait and see how the dust settles.
If an app/pluging/package is maintrained and published by X, I want to make sure no one else can interefere with it - even if they have good intentions.
What Automattic should have done is removed the plugin from distribution and told WP Engine to fix the problem. By doing what they did they have breached the trust of their users.