The arkenfox user.js is not default in Firefox because there are tradeoffs between security, privacy and usability. The Tor Browser is a Firefox that sacrifices

The arkenfox user.js is not default in Firefox because there are tradeoffs between security, privacy and usability. The Tor Browser is a Firefox that sacrifices some usability. The same goes for most other software. It would be desirable for all cloud databases for example to hide their data and what being searched from the server, but that can be only done securely with an unpractical (logarithmic) communication or computation overhead (using searchable encryption).