I will clarify this just because I have had several people ask me already. No, we did not remove the SyncFirst option in pacman to deliberately cause issues for Manjaro Linux. In fact, it was first discussed in Feburary 2012 and, as far as I can tell, Manjaro has only been around from late March 2012 (looking at the earliest commits in their git repository).
So lets keep the conspiracy theories to a minimum! (or at least come up with a better one…)