Regarding deprecated quests

In looking through the database and testing quests, I’ve found a few that are deprecated (and labelled as such). Are these outdated quests being left in the database for a reason, or just doesn’t help anything to remove them? Simply wondering whether I should report these or just leave them be. Thanks!

Blizzard don’t really removes quests, you can have the quest on one old char and complete it.

If a quest giver offers you a deprecated quests, that sounds like a bug that should be reported in the tracker.

No no, quest givers aren’t handing them out. They’re simply still there in the database - I didn’t know if they were being left there for posterity’s sake, or if they were planning to remove them at some point. They’re not hurting anything at all, just appearing as I was doing some lookups and making lists of quests to test.

At what point do you stop deprecating quests on 3.5.5?