My decision to move away from DDG was when they blocked a website due to Bing blocking it. The block was inadvertent. But it showed the flaw in relying on an external provider for all your results. You're just using Bing with a different UI. Kagi having their own index (plus being enhanced by several others), was a huge selling point for me initially. Truly separated from a reliance on big-tech and their whims.
Kagi results are entirely sourced from other indexes (mainly google and yandex), their own index (Teclis) is small and insufficient. I guess you fell for the marketing. DDG also claims to have its own index btw, but as you've noticed it's the same situation. It's basically useless and 99% of the results are straight from Bing.
The only smaller search engine with its own real index is Brave.
Sure, their index plays a small part of the equation, but they aren't reliant on any 1 index for their resultset. But sure, I guess their marketing worked.
The index was why I looked elsewhere.
The reason I switched to Kagi was because of their business model where I'm a customer not a product. So results are theoretically tailored for value to me not value to the company.