So as you pointed out and a few others have in the comments, console scrolling for the skill tree is slow and kind of annoying. 

It would appear that there's nothing to do at the moment, other than 1) Submit feedback to the team to encourage an update and 2) Use the joystick on a diagonal to jump around a bit quicker.

There are a [few instances][1] of people recommending feedback, [especially for a free floating cursor][2] (Destiny style) to make console life easier.

Both of those threads had responses from the dev team saying to submit feedback and or they are working on modifying it.

  [1]: https://www.reddit.com/r/FORTnITE/comments/6ozq7w/mapskill_tree_controls_on_consoles_are_clumsy/
  [2]: https://www.epicgames.com/fortnite/forums/fortnite-discussion/general-discussion/10241-skill-tree-on-ps4