Data on search engine market share is available, but I wonder what that looks like for Lemmy users in particular, who I would assume lean more technical than the average user, so probably use DuckDuckGo and alternates more than Google.
I use a mix of DuckDuckGo and Kagi. I'll also use ChatGPT, which can be good if you're careful to verify the answers it gives you as a check against hallucinations. It's useful for short, direct answers without ads or SEO bullshit.
I use Ecosia. It works quite well, and if I ever need to search something on Google instead (like a coin flip/stock ticker) you can just do #g or #yt for Youtube
They also plant trees and are carbon negative