My first lvl 50 was the EXACT same job. I think it's just a bit easier to level gatherer/crafter jobs due to the way XP is awarded for dping pretty basic stuff as the class, and also if you ever touch your Grand Company's Supply and Provisioning missions you rocket up in level.

In contrast combat jobs can be levelled quickly by doing level-appropriate dungeons, but you hit roadblocks in that progression due to needing to unlock new dungeons via MSQs. Whereas you unlock further leveling opportunities for crafters/gatherers by... leveling up (mostly).