I sometimes wonder if that 5% is something DDG and others can realistically solve. Perhaps the issue has less to do with engineering and more to do with Google being the dominant player over the previous 20-years (give or take). That's an awfully long time for one company to effectively own a product category and build expectations among users about how it should work.

FWIW I do get good results from DDG (sometimes better than Google) but that does require me to be a bit more thoughtful with my queries.