Do you really believe this is Apples paramount motivation? The only reason this is acceptable is exactly because they have nothing to lose, only everything to gain by hurting competitors that rely on advertising revenue. Ask yourself this -- if apple iAds was wildly successful would they be taking the same action? To ensure the "best web-browsing experience possible"?
> Better privacy for their users! Breaks analytics and ad targeting? Who cares?
Maybe companies that generate revenue using these tactics? Again if this was Apples bread and butter they wouldn't be implementing any security measures might interfere with their bottom line, user experience would surely be taking a back seat to profit.