This always ends up being a balancing act.

On the one hand, people want to be able to easily access the new content on the new class as soon as possible. So a high level start is wanted.

On the other hand, you still want to have people unlock their skills over a period of time so people are less likely to feel overwhelmed. So a low level start is wanted.

Personally, 50 seems like a decent start, because you have a reasonable semblance of a rotation with plenty of time to get a feel while you level up. Though, 50-60 leveling is pretty trash >.>

So 60 is an alternative that alleviates the horrible HW leveling period.

Also to note, the lower level a class starts, the better they have to 1) Fit them into the lore for the period (I.e. 1-50 is ARR timeline, 50-60 is HW timeline, 60-70 is SB timeline) and 2) Create more Job Quests for them due to more levels to level from.

To say nothing of the fact that, if someone does want to slowly access their skills, they can always go solo PotD. It's easy enough to solo level 1-60 in there which gives you your skills as if you started at level 1 but without that awkward massive timegate that is doing actual levels (Which, ironically, for most people would end up being PotD spam )

I suppose, if this trend of increasing levels and overwhelming button bloat continues they could always do what WoW did with Death Knights, which is, create an initial series of quests that unlocks your skills systematically rather than giving you them all the second you start on the job.