> Or in the "packrat project manager" scenario, there may be tons of low priority nice-to-have tickets that have been sitting around for months or years, even though everyone knows they'll never be worked on any time soon. If this is the case, the graph is still "sad", but it's not a death spiral... it's just a sign of a wasteful and broken issue tracking process.

What's wrong with keeping a few hundred "low priority" issues in your tracker as long as they are labeled properly?