POST requests make for better privacy,
when clicking on a result, the HTTP "Referer" header would leak the search query to the third party website.
Other issues related to logging may also be problematic with POST.
see:
https://support.startpage.com/hc/en-us/articles/5265503371412-POST-versus-GET
https://stackoverflow.com/questions/198462/is-either-get-or-post-more-secure-than-the-other
Also, please add a Privacy topic section in kagifeedback.org
Search and Privacy are supposed to be the main business at Kagi, so I guess it deserves a topic 😅
currently Kagi performs GET requests.
I'd suggest to switch to POST requests. (and just like startpage allow for people to switch to GET if they want to bookmark their search results)