Jump cues aren't the reason that NO AMERICAN PLAYER other than SVB can win anything and he can jump as good as anybody with or without a jump cue. A jump cue might determine the outcome a a given match, but it wont determine who will generally be in the finials... it'll be someone fro somewhere other then the USA and those Players aren't whining about them, their just winning.
Not sure you've said anything I disagree with.
I just feel that pool is a game meant to be played in two dimensions rather than three. The jump cue, too often, amounts to a full or partial pardon for position poorly played. I don't feel I've weighed in on the matter of which group of players the use of jump cues favors, and can't even say I've given the matter any thought at all.
As you note, the best players, over time, will win regardless of the equipment used, but as a serious fan of the game, I'm allowed to detest jump cues, which I feel detract from the majesty of the game.