Why a Library Variable rename does not update pipeline references?

hi JProvAnt 

Yes, based on current product guidance, this is expected behavior / a current limitation.
Fabric pipelines resolve Variable Library usage via static references in expressions, and if a variable is deleted or renamed, the pipeline won’t auto-refactor; the documented fix is to remove the existing reference and re-add it using the correct name.
So renaming a Library Variable can leave existing pipelines still pointing at the old name until runtime, and the safe workaround is to treat variable names as stable contracts (add a new variable, migrate references, then retire the old one).
https://learn.microsoft.com/en-us/fabric/cicd/variable-library/variable-library-troubleshoot#variable-reference-failure

Thanks and Regards,
Shreya