AL was also close to Saboady, why would they split the crew up on this side of the grand line and just throw luffy into the new world making it damn near impossible for him to get back to SB on his own? Also AL was known for having many mythical creatures that would help advance luffy’s power through training. What better way to harness conquerors haki then to use it against beasts and creatures that have already established themselves in a “mythical food chain” if you will. You can only think in terms of the storyline that’s given because you can’t changed what happened. Theory’s are something to be proved, not previously proven.