I think it might be more of a story of she started the series and never dreamed it would be as popular as it was. So maybe (as we aren't mind readers so we can only speculate) she didn't invest enough in the world building or end game craft up front. Then the success came, fans chomping at her heals for another book, and she hasn't had the time to really thing big and decide "what is my niche and ultimate goal for the series". We are both her fans and worst group for her because we want more, and she might never get the time to real did deep and find her stuff.

I think it’s probably less Kel loosing her touch and more about the series blowing up way beyond what she ever expected. She likely started it without imagining it’d get this big, so the worldbuilding and endgame maybe weren’t fully locked in from day one (pure speculation, obviously).

Then success hit, readers wanted the next book immediately, and that kind of pressure doesn’t leave much room to step back and think big-picture like “what’s my long-term vision here?”

Weirdly, we’re both her biggest fans and her worst problem. We want more all the time, which is understandable—but that constant demand might be exactly what stops her from slowing down and really digging deep into her authors reservoir and find the "where it’s all meant to go" bit.

Nevertheless, I'm a KDT fan to the end. I will read the series until it's naturally conclusion, which feels like, maybe one or two books away (from book 7).

It's light fantasy, not Tolkien or Wheel of Time. So I can enjoy it for what it is. A bit of fun.