If that isn't a rhetorical question... capitalism.

It has been like that for the long time, actually. I've seen examples where somewhat political search clause (in Russian) yields completely different results on Google & Yandex (it's actually hard to tell which one "tweaks" the results, and what tweaking even really means, when you think about it — my guess would be both, but differently). But in a sense of intentionally hiding something "neutral" that I know perfectly well must be there, but isn't (and it seems like you can guess why) — I've never actually noticed in on Yandex, while on Google it has been like that for the whole decade already. (I don't find is that surprising, really. To me, it's perfectly logical, but I won't elaborate, because it would be political and extremely unpopular on HN, which seems like a worthless flamewar topic to me.)

But in my experience Yandex just isn't as good at searching things in English, as DDG/Bing. At least, I always preferred them for most use-cases except from some really specific ones. So it's a pity that this thing with DDG happened. I guess, I'll still continue to use it for now, because I don't want to hurt my productivity other that thing (and switching to a search engine I would have to adapt to most certainly would do that). But we'll see.

I suppose that's a real use case for a meta search engine: send queries to different search engines, then interlace the results removing duplicates.

i mean yes, it's suboptimal. but hardly news that for the real deal, you gotta leave the main road.