You misunderstood his spost he SAID the AK-47 has NEVER actually appeard in a canon fallout game. Which it hasn't the only one containing an AK-47 was tactics which even the creator admited wasn't canon and applogized for how badly he broke from the series. The AK-112 an the Chinese Assault rifle are simply based of the design but not the same weapon.
It was already pointed out by Mako Vlazkov but I am going to say it again. Fallout Tactics is Canon! Bethesda said the "High-Level Events" are Canon. They also confirmed in Fallout 3 that there is a Midwestern Brotherhood.
Someone needs to write a letter to Micro Forté and the Devs of Fallout Tactics and tell them that they have been vindicated and that Tactics is a Canon Game.
If you are wondering why people for so long called Tactics non-canon is because of Van Buren aka the cancelled Fallout 3. It was going to have a very different interpretation of Cheyenne Mountain than what is in Tactics. Now Van Buren was never made, therefore is not canon. Tactics was made and therefore it's version of Cheyenne Mountain can't contradict Van Buren.