In the last couple of months I have noticed an increasing trend of supplying me search results that are completely unrelated to the current query and tie back to my location or previous searches. I can say this with a high degree of certainty this is without a doubt beyond the 100th instance this has happened.
My browser is configured against tracking and fingerprinting (in fact all my devices are) which would make it fairly difficult to retain any data unless they are profiling me.
As someone who is a data hoarder/curator and dives into the deep ends of web abyss, I use Searx, Startpage and Yandex. I do not mind Startpage only because I no longer use search engines that much anymore. If something truly needs to be searched, Yandex is the absolute, untouchable king for web, image and reverse image searching, and is better than Google for privacy (very low bar but > Google/Bing).
Searx usually does deliver for the common use cases, and Startpage gives Google results minus SEO and sponsored trash.
If I were to rank them for results based on years of experience, Yandex is easily a 10 (ignoring its unbeatable image search), Searx with “default/all” language results a 7, Startpage a 5 (censors Russian/Chinese sources since it is based on Google), Qwant probably 3.5-4 (unavailable in many regions), Google 3, DDG and Bing 2. I am not sure how Metager, Mojeek and Kagi fare, but they probably perform somewhere between Searx with “default/all” language results and DDG.
Why Yandex is so above Searx metasearch is because its indexing is a lot faster than once a day, besides giving the experience of what Google was around 2009/10 and with no SEO crap. You will find the most obscure personal blog and website there, and DMCA bullshit does not work in Russia, which would work on any of these other search engines or metasearch instance owners.