I think the bigger impact is not DuckDuckGo suddenly replacing Google but the EU making the search market more competitive
Google still has an enormous lead in Europe, but the DMA is forcing changes that make it easier for alternative search engines to compete and even gives eligible competitors access to Google Search data under fair conditions
For SEO I’d start watching traffic from Google, Bing, DuckDuckGo and other engines separately instead of treating “organic search” as one bucket
If alternatives actually gain meaningful market share, we could eventually have to optimise for several ranking systems instead of spending almost all our time reverse engineering Google
The interesting part is that the EU is also pushing competition around AI search, so I’d expect SEO to become less Google centric over the next few years rather than SEO itself becoming less important
I wouldn’t change my whole strategy because of DuckDuckGo yet though. I’d diversify where the traffic comes from and keep an eye on the data before making a big move