You could even argue that American players are actually worse, since they need a server-side aim-assistance system like Unlagged, whereas most European players just deal with the lag.
In the end it doesn't matter at all though, since any American player that really wants to play on a European server will most likely learn to deal with the lag, whereas a European player that frequents American servers will quickly adapt to playing with Unlagged. The good thing about having Unlagged is that it offers choice.