EDIT : I was able to work around this by maxing out upgrades on a bunch of different, random buildings (barracks, blacksmith, etc.). Still, I’ll leave the post up since this is only a workaround and the bug still remains.
I’ve done the requirements for this achievement multiple times (research everything in the house of wisdom) but it wont unlock. It seems I’m not the only one having this issue, as can be seen here: All the World's Knowledge Achievement Bug , All the World's Knowledge achievement in Age of Empires IV: Anniversary Edition
