Mozilla is very active on privacy advocacy and highlights Firefox’s privacy as a feature[0]. This makes some sense because the features of Firefox (cookie blocking, containers, first class ad blocking) all help preserve your privacy better than Chrome or Edge. As part of this advocacy space they’ve also done things like “privacy not included”[1] (the asterisk and lowercase are intentional, similar to the 1987 movie “batteries not included”).
Content-marketing / keyword stuffing, so when you search for "How to delete Instagram", you get on Mozilla website and get to learn about it and eventually decide to download Firefox, which will make money out of ads from Google Searches and other partnerships.
[0]: https://www.mozilla.org/en-US/firefox/privacy/
[1]: https://foundation.mozilla.org/en/privacynotincluded/about/