I've "lost" a few sites that way. Forgot the address, can craft several searches that years ago definitely would have brought up the exact site I want. But... nothing. Or it's buried so far in the search results I'll never find it. I need a good search on top of Google search, these days.

To be fair DDG rarely works for me in that way, either. I think that kind of old-school, precise search engine's just dead now. It seems like everyone's indices are a lot "fuzzier" and full of holes, like they're discarding large parts of pages from the index if those parts don't look important to the algo. Not just deprioritizing, but tossing those pieces out entirely. Except the algo's very wrong.

Yeah, I made similar experiences. Also to dive into some random topic, Google is not really helpful and just suggests only really obvious things first like Wikipedia.

On the other hand, for day to day work at least for me it is still indispensable. Googling a random exception out of an unexpected stack trace works far better than with DDG for instance.