We currently use List all contact activities to get all email activities like email sent and opened etc. It kinda works however it isn’t an ideal way to pull millions of these actions at once because it returns a lot of other activities and you can’t really do a “before date” filter.
There is also List all email activities however it doesn’t work when you don’t specify a contact.
Ideally, we would want to pull all email activities (no need for the content of the email, just subject with tags/categories is fine) in batches along with their contact info (either id or email)