While I agree with people that say that it's optional to use the slower world travel. I think you are missing my original point: Not only would slow travel be more immersive, but also slow progression down. I would much rather spend my time traveling around Eorzea and thus not have to wait for latest tomestones to become available again after having capped them for the week. Or only being able to loot once per week in the latest raids.
I just think it would provide a more natural way to slow people down, instead of these weekly barriers. Not to mention the insane grind like 5 billion tomestones trades for that next whatchamacallit so we can get our next relic upgrade. Keep the airships and the porters. But get rid of the insta-travel that keeps players from enjoying the scenery.
Im playing Morrowind atm, and it feels so much more immersive playing having to travel to the nearest slitstrider-bus to get to the next town. And if I wanna travel beyond that I need to make a bus-change.