[release-20.0] refactor: cleaner cloning API (#16079)

[harshit-gangal]

Description

Backport of #16079
Needed to backport the Regression fix #16049

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[frouioui]

Although the refactor does not seem risky, let's not backport this to 20.0. It is also not needed for the subquery fix #16049 on release branches.

Closing this for now, feel free to re-open if needed.