Noone's talking about plattforming in the context of jumping in MMOs.
The most important part is more freedom of movement. Think back how XIV was a few patches ago, where your characters couldn't climb even knee-high ledges, and would constantly get stuck at things in the environment. They patched it now so that they can just run over those. Other games would have used jumping for that.
People talking about Mario-style jumps where one is jumping 3 times the height of the character are just making strawman arguments. That's not what this is about. Enabling players to get over obstacles with a small hop means the developers can be a little more lenient when designing the world. They can use more props and solid elements with collision detection without the danger of obstructing the players path.
