With 6277 stars, Android Issue 82 had its status changed to Obsolete. This was part of a sweep that closed a large number of "popular" issues, which was covered by both HN and Reddit.

I am no longer working at Google, so I have no insider info here, but I can share that the key difficulty in bringing (the old kind of) ad-hoc mode to Android is the combination of historical neglect for it by WiFi driver vendors (leading to stability concerns) and lack of strong product lobby. Most advocacy for ad-hoc comes from researchers and innovators in off-the-grid communications, who recognize the flexibility of the ad-hoc mode, but it remains a niche albeit compelling application.

For mass adoption, battery concerns are a pressing issue, although they could certainly be addressed via standarization of power saving modes. That said, I suspect a combination of BLE (with low power, throughput and latency) for discovery + Wifi Direct (high latency and throughput) for bulk is the best candidate for proximal networking in Android today.