After some EXP balancing, FATE trains for leveling up stopped being a thing years ago. Long before cross-world travel, I think during the transition period from ARR to HW. Dungeons and specifically roulettes became the main way to level up.

BLU and adding bicolor gemstones to FATEs were an attempt to bring people back into the overworld but those only get traction around the time there's a BLU update or a new expansion comes out.

Hunt trains bring people together from all corners of the data center so I'd recommend finding a hunt LS if that's something you want.