I get Kagi since you pay for it, but doesn't using a logged in account with DDG defeat the purpose of using DDG? How does having a search history associated with your DDG account improve things? You're just moving who knows your search history from one org to another

If you are not logged in, your search history may be "not associated with you account", but it still is associated with you.

It's more a matter of whom do you trust. Private mode in browsers still gathers unique user IDs, fingerprinting is widespread and fairly precise. The "logged in" part doesn't change that much.

You don't need an account for DDG. I assume the record keeping for which sites you exclude is cookie or session based.