The framing of what a Threads account *is* strikes me as a funny thing.
Meta is saying "Threads is the fastest growing app in history with 100M users in five days". This doesn't make a lot of sense when you consider that a Threads account *is* an Instagram account.
If you accept that Instagram has 2 billion active non-EU users, the story could easily be "Only 5% of eligible Instagram users opted in to Threads in five days".