I tried Kagi for a while, but it was giving me less useful results than DDG, so I simply left it. I think it depends a lot on what kinds of searches one does, and Kagi is more useful for other users.
I've been using SearXNG during the last day and I'm quite impressed too so far!
True what you say about the problems behind net search. It's actually a very complex problem. In my opinion part of the problem is that there's a lot (most?) of rubbish out there. It's like a library with useful books of different genres all mixed together, and mixed with an even larger amount of nonsense books. Maybe a solution would be something completely different from indexing – but I have no idea what.
It's very likely to depend on the kinds of searches I do, indeed. Although I think it's the same as in the previous years. Could also be just a subjective impression, so I'll try to keep count of how often the "!g" really leads to better results.
I'm trying SearX today, after so many recommended it. It looks promising! Thank you for pointing out the multiple-engines setup.
One possible drawback: it seems I can't do "verbatim" searches; or at least, quotation marks don't seem to lead to verbatim searches – I'll try with "+". DDG was adamant with quotation marks, that's something I liked a lot about it.
Trying it these past days and I'm impressed!