CalculateSX
The CalculateSX extension, which can write aggregated values directly to any business object (for example, filling a cost field on an order), will not be added as standard product functionality.
Reasons
It relies on direct database queries, which are risky for performance, security and stability, especially in cloud environments.
Implementations of CalculateSX are highly customer-specific.
Supporting this in product would require an API that basically opens direct DB access again, which is not desired.
Instead, the direction is:
Use Platform business rules where possible instead of CalculateSX.
Or:
First create aggregated data via the regular Data Aggregation process (ReportSX replacement).
Then use a Platform extension to read the aggregated data and fill the target fields.
Implication
If you currently depend on CalculateSX, consultants will likely refactor your setup.
In most cases, the new approach will run on a schedule rather than real-time, which is usually sufficient for reporting and analysis.