While i'm neither for nor against level sync the ones that feel it will overcrowd camps are thinking too much about XI mechanics. Same for those talking about smn burns.
XIV will not use camps to grind for xp like XI and there is no smn or smn 2hr aoe like ability. Unlike XI level sync can better fit this game's design without so many exploits.
Note: Even in XI you couldn't sync to lv 1 so that holds no viable argument to write down as a con.
Edit: Level sync would also make maxing out behest xp gains for everyone a lot easier and could even help up the difficulty a bit more.