There were two questions related to the Semitic Languages proposal which were also linked to the old proposal on that topic. Now that the old proposal has been removed, those questions have been removed, while they were still relevant to the new proposal. In fact, I made a big deal about keeping the references as useful and complete as possible.
This is odd and unexpected, and there is no way to undelete the questions yourself, as far as I can see. Therefore I would suggest it is better to not delete questions that reference at least one not-deleted proposal, or, alternatively, to give posters of questions that are about to be deleted a one week's notice, so that they can update the references if they want the question to be kept alive.
- Do not delete discussions about deleted proposals (the present feature request is different because it still proposes to delete discussions that do not link to any active proposal)
- Is it possible to resurrect a discussion question from a deleted proposal if it also referenced a current proposal? (the present feature request is different because it asks to make this the default strategy)