Why is merging accounts actualy not merging?

Normally when you merge things you make a whole 1 of 2 or more others. Now is till have 2 accounts mixed under one login which is confusing and annoying.

And for some reason the default was not the main account, so now I am stuck on an old account while most of my cosmetics are on the other one. Why can't you actually do a real merge of the 2 accounts? Clunky as hell this is.