Things like irrelevant results, inaccurate or outdated information, missing or completely incorrect information, or just information that doesn't contextualize the queries properly. For a start. Do you think search engine optimisation is just a google thing or what? Because I have news for you. Seo is a problem for all of the search engines. So are irrelevant results, failure to contextualize queries, and just receiving incorrect or missing information. None of those problems get fixed by switching to duck duck go, or bing or kagi or whatever. Can I avoid the AI LLM BS? Maybe. But having tried alternatives I just don't find them to be particularly better. In some cases, especially for my work I find them to be worse.

Stop saying "alternatives are available". If I search for an AP article using search terms "apnews.com: senator visits Taiwan" I should get news articles from the AP news website. Even if those are from 2014. That's contextually accurate to the search query. I get articles from a fair number of websites and news outlets. I don't want those. Know what I don't get? Articles in chronological order from when they were written, from the AP news website. I don't want anything from twitter or Facebook or Reddit. That's me trying to use a search engine to search a specific website. Same thing happens when I search for a gif on imgur.com using imgur.com: "search query" in the search box.

Years ago I tried to use google and duck duck go and Bing to find information about some nonsense someone at work was spouting about congress attempting to pass a pro child molester bill. Not only could I not find anything relating to where this was being reported and what nonsense they were bastardizing to come to such a ridiculous conclusion, I couldn't even find actual bills relating to things like anti-child molestation legislation. I had to actually search the congress website and then use key words on the website to find what I was looking for.

Try looking for a sort of popular anime from the early 90's that you can't remember the name of. You get a bunch of top ten lists. You get anime that came out well after the time period specified. You get random fanart. You will absolutely not get the anime you're looking for unless it was really really popular. The alternatives all give varying degrees of the same results.