Another commenter summed up my feelings on PL/SQL. It's not that it's inherently bad, it's the bad practices that seem to follow.

Modernization to me (specifically in the context of the GC) means refactoring/rewriting systems to follow modern industry standards and practices. Things like proper version control, automated testing, automated/semi-automated deployments, and monitoring and logging.

I think there are major benefits in adopting these practices for both the Canadian public and the developers building/maintaining the solutions. Unfortunately, getting a budget to move the source code from a shared network drive to Git is next to impossible. And God forbid you want to spend time adding any sort of testing.

The stack itself is rarely the problem, sql scripts and triggers in these kind of systems as op says is not properly version controlled or documented. In a refactor or revamp these are discovered along the way