It's more pay-to-play than "cultural imperialism". Arabic does seem to suffer due to no primarily-Arabic country being a member of the consortium (IIRC and it hasn't changed in the last five years). If someone was willing to absorb that cost then they could almost certainly get things done (e.g. look at Japanese).

While the pay-to-play aspect is obviously not utopia, it does seem to work quite well in practice: Arabic does have a large amount of support as is; to get more, you really need to have people who use Arabic as primary members so they can make the hard decisions.