Rewards for a pool are paid into a single rewards account controlled by the pool operator. If the pool operator and pool owner(s) are different people, we need to properly calculate a way to split rewards between all the owners.
How can we calculate the total overall rewards a pool made in the last epoch? How do we calculate the delegated stake of each owner for that epoch? How can this be calculated retroactively if we need to look back at past epochs to see what the delegated stake was?
There are many complexities to ensure rewards get paid properly. For example, one owner might want their rewards sent to a separate account while another might want theirs re-invested in the owner’s pledge account.
If possible, this information should be available from cardano-cli. Running a heavyweight server like db-sync just to get some payment numbers is problematic.