What are you comparing it against? Do you actually have a better alternative or just having a bad day?
The fact that you tried to pick on 2 of the results for such a generic keyword, show that it's miles ahead of mainstream search engines which are filled with SEO spam.
I tried that same search on Google, duckduckgo, bing, brave, yandex, even yahoo and needless to say the results were pretty much all SEO spam, list-style keywords farming from generic websites such as NYTimes (how tf is NYTimes an authoritive source on purchasing headphones?). Whereas in Kagi you get a wide range of helpful results focused around reviews/enthusiasts/forums, here are some of the results: youtube video reviews, reddit discussion, discussions on sound design forums, a Quora qusetion, the headphones page on best buy, amazon, walmart, etc.
And as the other comment said, Kagi also has life-saving features that empower the user to have control over the search results [0]. As far as I know the only weak point in Kagi (at the moment) is doing more local-focused searches.
Regardless of the quality of results (which mind you, are already quite superior), it'd be still worth paying for if only to support its ad-less search model and help nurture it. Prove that it's a viable model for the sake of the web. For everyone sake. It's a great effort for that alone. Combine both the model and high-quality results and it's the best in class with no one even close.
[0] https://help.kagi.com/kagi/features/website-info-personalize...