After seeing this LinkedIn post, I can share some good news. Emails in Dataverse are now being stored in the blob storage instead of the database. This change will save a lot of (expensive) database capacity.
This wil save us a lot of (expensive) database capacity for ActivityPointerBase.
The data migration from Dataverse relation store to Azure Blob storage for all customers is expected to start in May 2023. This data migration will take place as a background process. The initial data movement for existing customers is expected to last for about 6 to 12 weeks, and possibly even longer depending on the size of the data. After the initial data movement, any remaining migration is a continuous process. All email descriptions older than 12 months will be moved into Azure Blob storage automatically. Newer emails will not be moved until they become 12 months old.