Depreciated is not removed. Apple is usually very conscientious about depreciating things, then waiting a while before removing them. In some cases they have gone to great lengths... for example the now 5 year depreciation of OpenSSL: first they marked it depreciated, which generates a compiler warning, then after a few years they removed the headers from the MacOS SDK so you couldn't compile new software but left the binary in place so that old software would continue to work. The next step will probably be to remove that binary, something I would expect in MacOS 10.13 (sometime this year) or 10.14 (presumably next year).
Poor choice of words then, it was deprecated and removed over the course of iOS 9 betas, with the plan to make a new system only available to "captive network apps" that could declare a specific list of SSIDs that they manage. Appears they backtracked though? I didn't see any recent info.
