And what would you suggest as alternative, given that normal users (e.g. people who've never even heard of HN and make up the majority of browser users) expect to search with Google?

As far as I recall, the Google search is part of the funding agreement (because Mozilla is still a non-profit, the money has to come from _somewhere_ and we, the users of the browser, sure aren't paying them?) with the explicit agreement that it is trivial to change the default search engine for people who don't want to search with Google.

Click on the drop-down on the left of the search field in the browser, you click "change search settings", you pick your preferred search (options for which include "duck duck go" these days) and you're done forever. That... feels like a perfectly fine way to go about offering people what they want: make what the majority wants the default, and make it trivial to change for people with different wants or needs.