Ouch. This reminds me of a coworker of mine: they were born in one country, grew up in another, and then moved to the US. Despite only being here 5-ish years they speak perfect American English with no accent. However they are missing the last 20-30 years of American culture. They’re extremely smart but every now and then a conversation will trip up and we’ll have to explain something like “these guys are as bad as beavis and butthead.”

Now Achilles is a little better known than beavis & butthead but I don’t know how much Greek mythology they read in different countries. Especially the ones pumping out STEM geniuses like my coworker. Wow is all about catchphrases and references so I could easily see how an otherwise extremely intelligent guy could totally bomb like that dude did.