On a related note, what does organic search traffic look like these days? I was once personally invested in running several small content sites and at the time organic traffic was pretty much entirely from Google. There were other inbound sources - Bing, Yahoo!, etc. - but they were so negligible that it would have been reasonable to ignore them completely for the purposes of optimization.
I've been using DDG as my primary search engine now for several years, and using Google no longer "feels like the Web" for me. I imagine I have one hell of a case of observation bias in that, but it does seem like alternatives have been gaining some traction in recent years.
That said, looks like most of the US does not feel the same way about Google. I still see 90-99% of organic traffic coming from Google for my client sites.
It's still 90-95 percent Google, surprisingly. You'd think it would be less with mobile but no. We are seeing more duck duck go, but bing and yahoo have stayed steady for years. Social is a rise, and that's a lot of mobile. Also then just pickups (links from sites like this). But yeah, still very much google dominated.
I've been using DDG as my primary search engine now for several years, and using Google no longer "feels like the Web" for me. I imagine I have one hell of a case of observation bias in that, but it does seem like alternatives have been gaining some traction in recent years.