Other than the MS trackers, how does any of that impact privacy?

As for the MS thing, they did fix it:

https://techcrunch.com/2022/08/05/duckduckgo-microsoft-track...

and they were never part of the apps. They previously whitelisted microsoft ad and tracking domains in their browser.

I read through the linked article, and although they did seem to address the MS tracking somewhat, it looks like the state of DDG is even worse. It has all sorts of MS tracking stuff baked into the search itself with the whole thing seemingly just based on MS doing a pinky promise not to use the data they're getting.

That's not true - there's no way for to make search histories from DDG searches: https://duckduckgo.com/privacy

> Despite this expansion of DDG’s ability to block Microsoft tracking requests, there are still instances where Microsoft ad scripts are not blocked by DDG’s tools by default — related to processes used by advertisers to track conversions (i.e. to determine whether an ad click actually led to a purchase).

...

> DDG says it wants to go further to protect user privacy around ad conversion tracking — but admits this won’t happen any time soon. In the blog post Weinberg writes that “eventually” it wants to be able to replace the current process for ad conversions checks by migrating to a new architecture for assessing ad effectiveness privately.

From the linked article. Which points us to the ad disclosure[0]:

> If you click on a Microsoft-provided ad, you will be redirected to the advertiser’s landing page through Microsoft Advertising’s platform. At that point, Microsoft Advertising will use your full IP address and user-agent string so that it can properly process the ad click and charge the advertiser.

followed with

> Microsoft Advertising does not associate your ad-click behavior with a user profile. It also does not store or share that information other than for accounting purposes

Hence the pinky promise. I'm good on all of this personally.

[0] https://duckduckgo.com/duckduckgo-help-pages/company/ads-by-...

Brave is not secure or a valid option imo

Care to elaborate?