my account is vet SL capped, also F2P account attached via Bnet. all players had the quest start at the main city FP in BFA, other day i made some 10's and 20's to check. all the alliance that zoned into SW had the mechagon start in the ambassador building in SW. i attached a SS of a 10 i made just now of a
level 10, just arrived, quest in SW embassy. now a GM might say it's for allied races only but not the case for me, older races at 10+ i got the unlock at main city FPs
added another SS, of the same 10, did not take the quest in SW, started the BFA intro line, did the skip at SW harbor, after i unlocked the sanctum of mages in snug harbor NPC at the quest appeared near the FP
i do have some drak race players i made during the 3 days free, but i never took them past 58 or did anything, i have never bought the FP BOA unlock toys for any expac
alot fo GMs at times are not aware of the changes done in the game. they may also be speaking in legalize at times. technically mechagon unlock is not account wide. but, having done it on higher level player techincally enables a skip for alts to directly to start the mechagon unlock directly. obviously months back they opened mechagon for leveling level 10+ they made the NPCs appears in SW embassy and main city FPs. had to be a blue post, or mmo-champion, wowhead, etc announcement. i discovered it was unlocked when i saw the gnome quest giver at snug harbor FP.
blizzard had to get bug reports or GM tickets back in Sep 2023, the alliance side was bugged after you did the quests at the vault and could not continue, horde side was bugged at mechagon during the unlock quests and could not go past the drill rig construction. those were fixed along with some other things.