You have got no clue at all, do you? If everyone goes strength, than using short weapons is easier, because people are slow as hell.
This is why EU is more advanced, if you go full strength there, you will get your arse kicked by Phyrex, Bjord, Greifenherz, Atze, and all the other players who went for 21 agility.
Get your facts straight.
I think the main issue is that NA "evolved" a different way, as NA has a noticable range spam compared to EU so AGI builds are often shot to pieces, so people started moving away from them and towards higher HP builds with armour.
I don't think the AGI EU or the STR NA are inherently more "evolved" then one another, as high STR builds get trashed in EU still and high AGI builds still get trashed in NA. It is just two semi-isolated communities who have evolved in different ways, no one build is better then the other, and Walt has proven with one of his "papers" that even a 0ATHL character will walk forward faster (as long as he only blocks and times his strikes) then a high ATHL character can backpedal, so it is not like it is a hopeless cause.
EU went the way of Oranges, and NA went towards Apples, both good but both different, it is just that EU is accustomed to their own playstyle and so is NA and thus is more used to squeezing out extra performance in their own different niches.
Good players will still do good no matter if the go high STR or high AGI if they are used to that particular build.
Stop this "evolution" bullshit that keeps popping up every month. This is not evolving, this is adapting a preference.
The only clear differences that have not to do with personal preference on the servers from my expereince is that NA is more used to Range spam and has fewer people who keep standing dumbly when shot and can dodge properly, and that EU (even the EU folks who visit us say this) has less greedy cav who team bump their own team mates to death.
TL:DR NA top players still dominate high AGI builds and top EU players still dominate high STR builds... Think about it...