Why does DDG not present "direct" URLs in its search results?
Why does DDG, like Google, by default instead prefix all results with a URL pointing to DDG servers enabling DDG to track what results that the user clicks on?
Google started doing this some years ago, e.g., all the URLs in search results are prefixed with something like https://www.google.com/url?q=
Needless to say, this serves no useful purpose for users and it showed the direction the company was moving in.
Easy for any nerd to remove client-side, but it is on by default and this will catch many non-technical users who do not know about them or how to remove them.
In DDG the prefix is something like https://duckduckgo.com/l/?uddg=
Even assuming no logs are kept with client IPs, and no correlation can be made by any party in possession of DDG's logs bewteen client IP and clicked URLs, this practice is still collecting data. The data collected is not merely what searches a user submits i.e. search data, but also data about the user's browsing, i.e., which URLs she chooses to follow. And of course it collecting this data without asking for the user's permission.
If the company can argue having this data is useful to the company and therefore somehow useful to users because company will make better website/software (a common argument made by many web companies caught collecting user data by default), then it seems the respectful thing to do is ask users if they want to contribute such data. Let users make the choice.
As I recall this default prefixing of results is not something that search engines before Google used to do. Nor did the original Google do this either. It is something that Google started doing some years ago.
Note: Some browsers allow the user, e.g., to preset a default HTTP referrer, to set it to the target URL, to send an empty one, or to not send this header at all. Same options as offered by "meta referrer" except it is controlled by the user in their browser, not via a third party website. I have no idea if the popular browsers have such settings.
Finally, a problem with having bad design choices (such as prefixing URLs) and then offering users the option of changing the "settings" via a website is that this usually requires Javascript or cookies, because as everyone knows HTTP was designed to be stateless. Cookies and Javascript are two things privacy conscious users may want to avoid. By default DDG does not set cookies or require Javascript. (Good.) But if in order to change a bad default, the user has to enable cookies or Javascript, then we have sacraficed the goal of no cookies or Javascript required. (Bad.)