I've got a draft email to the powers that be suggesting something similar. It's a work in progress while I work out the reasons for keeping them. I suppose one reason would be that someone could be using a module, unaware that it has been deleted. Bugs, patches and coversations submittied via RT would still be available for reference. As yet this is the only sensible reason I can think of for keeping them. Thanks for your input.

Update: Raised as a meditation.