(Am author) Most "alternatives" to the big three search engines (Google, Bing, Yandex aka GBY) just proxy their results from GBY. I took a look at 30 non-meta search engines with their own crawlers/indexers to find actual alternatives.
Gemini link: gemini://seirdy.one/2021/03/10/search-engines-with-own-indexes.gmi
Feedback + additions welcome.