Reminder that this is revenue, not profit AND it is a fine from the EU so really only EU revenue should be counted when discussing how hard this hits Meta.
Even if the calculations for how to attribute income from different places would be difficult to decide upon precisely, and doubly so if the calculations are used to determine a penalty fine thanks to the possibility of being gamed, it can probably be guessed at without too much error in cases where Goodhart's Law doesn't bite.
> a fine from the EU so really only EU revenue should be counted
You can't really fully seperaten EU revenue. I as a European write very intelligent and relevant posts on Facebook, thus people from other regions go there to read them. (well, I don't post anything on Facebook these days, but the point stands)
Meta revenue is from showing an ad. "Is the ad shown in the EU?" seems like a pretty clear line. IFRS rules already require tracking the action that recognizes revenue so seems hard to play games with it.
Yes the fine should be based on global revenue, but when discussing if this fine actually hurts Meta, you should try to estimate the EU revenue, because it is about if it Meta cares about the fine. If it is a significant part of EU revenue then Meta should want to comply or leave the EU. If it is not then Meta doesn't care.