Actually, how to handle issues is key for the enterprise, but Github doesn't invest in that feature because any serious development team uses something different (better) like JIRA. Most Apache projects also use JIRA and they seem to be doing just fine.
That's something of a confound, though - JIRA requires licenses and is preferred by big shops with a lot of resources, so you'd expect it to be better just by virtue of having more people paid to manage it.
I've seen plenty of JIRA projects full of the same mess of open issues, etc. as well, and that seemed to run exactly like GitHub: not enough people felt it was their job or had enough the time to spend on ticket gardening.
the problem with JIRA is that allow well intentioned but misguided teams to shoot themselves in the foot big time. A properly configured JIRA will work much better than Github's issues at its very best. It's kinda my specialty to take disorganized teams and help them perform better, and JIRA is one of the tools I use the most. It's very configurable (to dangerous extents) and can do pretty much anything.
Triaging is always a necessity, but the amount of work needed can be various orders of magnitude different depending on the quality of info provided. Making it TOO EASY to file bugs usually brings quality of the reports down quite a bit, too hard and it just discourages people. The amount your team can live with varies depending on the personalities involved, but Github is universally bad. As a manager every time I deal with a team that uses that system I KNOW I'n in for a lot of pain and I will need to bug a lot of people to get the gist of the situation.
I don't disagree that the GitHub issue tracker is too minimal. I would just be surprised if the situations where you've had problems also weren't situations where the development team would have neglected any issue tracker due to staffing or cultural problems.
