https://www.alexa.com/siteinfo/duckduckgo.com
It's also built into browsers. So, whatever they're doing, it's working.
So, do something different. It's possible to grow by endearing yourself to geeks first. How'd Firefox catch on to begin with? Geeks, then they recommend to family and friends etc.
Hell, even if geeks were their only users, it'd likely be viable. There are a lot of us.
Or, in my case, parents ask their kids to set up their computers and they install firefox and add things like adblockers.
I've been using it full time for a bit longer than two years. In the beginning I think I had to use "g!" to search on google maybe 1 / 5 times, now I really only search on google maybe once a month and when I do I often don't find any better results. It's really come a long way from the first time I tried using it 5 or 6 years ago.
At this point it's good enough that I think I could recommend someone else switch to it without needing to change their search habits.
As to DDG vs. Search, maybe this is a bit programmer leaning; however, I'd say that was some of the draw that got Firefox and Chrome to own the web browser market. They presented products that developers and techies enjoyed using and always kept them (initially) in their vision. I recall telling my parents they needed to switch from IE to Chrome because "it was just better" a decade ago. So, while this brutalistic terminal version of DDG only caters to a niche market, it's the same niche market that ends up spreading why it's the "better" product.
DDG has so much momentum behind it now I dont understand why they dont do all they can to create a search engine all their own(bulk up search engineers.. bulk up on venture funding...make acquisition that improve its search, etc). One that is as good or better then Google. I so want to be able to keep recommending it yet not have to hear friends/family say its not as good as Google.