I do everything in my power that it doesn't, but your point still stands.
My somewhat creepy story about this is that at some point I got lots of COPD related search results and ads and I didn't even know what this is at the time. After a few weeks my neighbors wife died from it.
I can only assume that my neighbors and other people in the house searched for it a lot in these weeks and Google thought I must be interested in this topic too.
Your average DDG user is somewhat privacy conscious, so they probably know much more about tech tan your average Google user, and are a lot more likely to be a programmer than anybody studying literature.
If you base your algorithm purely on what results get clicks (but not on who clicks them), you essentially target your average user.
I don't remember whether DDG does anything to the scores it gets from Bing. They might, but then - taking into account how particular its users are... - the poor Franz K. would be on the third page, far behind even a Kafka library for Franz Lisp. (No, that's not a thing. A shame, I know.)
Even if you turn off all tracking and use a private window, there are ways. In my case, the combination of a Polish IP address, Safari on Mac OS and English as the browser language is enough to profile me as "tech-savvy, probably interested in science and edutainment, not in funny cute cat videos, Polish politics and sports." The Youtube home feed is a testament to this. If I change my location to the UK (with a VPN), that feed suddenly becomes a lot more generic.