Man, screw this headline.
Literally in the news post on Steam, it says:
What About Assassin's Creed III Remastered?
Achievements for Assassin's Creed III Remastered are coming soon!
So while factually an accurate headline, it's implying something else. More accurate would be 13 years on, Ubisoft adds Steam achievements to original Assassin's Creed III, with achievements coming to AC III Remastered soon too.
Disclaimer: I hate Ubisoup games and I haven't bought a single game since Far Cry 3