Considering each gathering profession is its own class, and one involved picking herbs/cutting wood, and another mining ore… yeah, you can hit max level in those classes by doing just that.
But yeah, if you want flight, you have to do the questline. If you want flight in WoW, you are forced to do- lots of rep grinding, lots of WQs, all the questlines for each of the initial zones, and wait a year- plus more rep grinding with this patch (and exploration, but honestly, that takes a few minutes), plus be of level for that patch.
So no, if you were to make an entirely new character- it would take longer to do WoW’s PF. If we were to assume you wanted each xpac’s flight in FFXIV, and each in WoW- it would take considerably longer to level, get PF per xpac, etc… in WoW than it would to do so in FFXIV, unless you get to the point of having dozens of characters.
Even if we look at it on a per xpac basis- to get through say, ShB story, unlock flight, compared to just getting through all the PF requirements for BfA and waiting a year- you could get a dozen characters flight in FFXIV if you really wanted to before getting a single one in WoW.