I think the answer is easy lack of development resources and money
There are a lot of things that could be improved in Wikitree if you had development resources.....
Check the database error project for errors that exist in the database most could have been avoided if you had more validation when adding or importing profiles....
I yesterday found that a lot of Gedcom imported profiles are more or less not readable and have CONT in it. CONT is used in GEDCOM to tell it will be a new line please also read that....If you search using google site:www.wikitree.com/wiki CONT you get About 87 600 profiles has this garbage characters.... why don't we just clean it away with a program (as you always can restore a profile a program will not harm Wikitree)...
As Chris is the father of Wikitree and the one sponsoring and leading the development he is the only one that can tell us what will happen in the future.... and how much it will cost to do the changes and how we could contribute....My guess is that the Wikitree project has been growing faster than Chris thought in the beginning.....
A world wide tree the last 500 years is a crazy big project. Yesterday we had the eurovision song contest in Stockholm it has since start have had songs in 61 languages then you start to understand how complex the world is.....
Doing a genealogy world wide and agree on what is added is a challenge and I hope Wikitree will find a development model and a way how to sponsor a project like this.... and add more functions to Wikitree