Imagine you're reading a research paper, and each citation of a retracted paper has a bright red indicator.
Cites of papers that cite retracted papers get orange. Higher degrees of separation might get Yellow.
Would that, plus recalculating the citation graph points system, implement the "cascading deletes" you had in mind?
It could be trivial feature of hypertext, like we arguably should be using already. (Or one could even kludge it into viewers for the anachronistic PDF.)