Every once in a while I get an email about a ten plus year old bug finally getting fixed in some open source project. If it's a good bug accurately describing a real thing, there's no reason to throw that work away rather than just marking it lower priority.
In what world is adding a custom field to a bug tracker and maintaining it cheaper than anything? If someone proves out this workflow and releases a bug tracker that has the functionality built in then I'll consider adopting it, but I'm certainly not going to be the first.