It looks like the Meta was the official distributor / licensee for Turkey, and the ads warning about the region lock certainly have Atari logos on them. So I'd

It looks like the Meta was the official distributor / licensee for Turkey, and the ads warning about the region lock certainly have Atari logos on them. So I'd say it's fairly official, if not Atari directly then an affiliate. I was personally wondering if main reason for the the region lock was Meta wanting to lock out European games, or Atari wanting to lock out (cheaper?) Turkish games from the European market. Either side has reasons to want it. I'd also kinda note that although not a direct region lock, AFAIK the way the 2600 handles video timing (generated by the game programme, not the video chip) would have basically mutually locked out 50Hz and 60Hz regions at the time, as 1980s TV usually didn't "multisync" (plus there are palette differences between PAL/NTSC/SECAM systems as well).