I think we've been slowly moving back towards "keyword engines", coupled with spell check. I don't know how many times I have used a search engine myself, type a completely legitimate word that is not in their curated database, and it is changed to something else. Even if I click on "did you really mean", and get a different set of results, it pretty much returns garbage because they don't know what it is. This really hurts when you are searching for a technical term. Also, it's getting harder to search a phrase, it starts punting after the first few words, even if you try to force it in quotes. This again shows they care more about the word matching against their database.
The thing that set google apart in 2000 from the rest of the search engines (well almost all of them, a few were doing the same, but google had a 100% clean site) was that they crawled the web and saved down copies of the pages it came across, and actually did a legitimate search within the content of the pages. You could find anything then. I think they've essentially dumped that capability due to abuse and that they'd rather use keywords so they can sell them to advertisers (which is like the old 90's walled gardens if you think about it)
DDG has been sliding into complete garbage results for the past few years. Initially they were more of a search engine aggregator, but then they seemed like they wanted to be the next google, and were actually producing decent results. But now they are about the worst of the "big" search engines now. I have been thinking the reason is whoever they were using to collect data was sabotaging the data fed to them, because it was that bad the last couple years I used them. I haven't even really used them for about a year now. Even google is better, yes.