Earlier quoted context omitted.
For anyone reading this thinking "what a killer feature I need to switch to DDG now". All browsers do this natively now. In Chromium engines it's found under "Manage Search Engine". In Firefox it's under "One Click Search Engine".
My Firefox install has seven search engines by default in the "one-click search engine" options. By contrast, DuckDuckGo has 13000 bang shortcuts. Sure, you don't need all of them, but I use dozens: some of them almost daily (like !w for Wikipedia and !wt for Wiktionary), some sporadically (like !tw for Twitter or !a for Amazon) and some of them only rarely (e.g. I picked up a Pokémon game recently and consequently h…
For example, just used HN's search bar, and there it showed up in the options ready to customise keywords to my liking (if I wanted to change it).
Before anybody claims it's an additional step, it's not. DDG requires you to know what the keyword is before you use it, which is the same as having to use the search on the site before. So I guess I agree it's a killer feature if you exclusively use Firefox for the time being.