The average user doesn't understand search engines then. It's expected that any search engine will prioritize certain results over others, because that's the entire point of a search engine, it filters and ranks sites.
"Unbiased" is doing a lot of work here. I think DDG's messaging about that could have been better, and they could have better indicated what was going on when they used that language -- but to be clear, there has never in the entire history of DDG as a browser been a period where they didn't rank political content and where certain political sites weren't given higher search rankings over other sites.
There is no betrayal here because this is just how search engines work. There couldn't have been a period where DDG wasn't ranking political sites because the only way for a search engine to avoid ranking political content is to not return political results in the first place (never mind the conversation of what does and doesn't count as "political").
At most what we see here is that DDG was a little too eager to lean into people's misunderstanding about what they meant by the word "neutral", and too slow to correct people who took something away from that phrasing that wasn't true.