As it relates to protecting privacy, I believe that Firefox and/or the browsers based on it are the only viable options. The objective evidence for that has already been presented time and time again in various topics including the Which Privacy Browser topic. I don’t really feel the need to write a book about it every time. Especially since privacy is such a complicated topic that not everyone understands or cares about.
The high level reasons for that are:
- Firefox has privacy related controls and add-ons that aren’t available on Chromium-based browsers.
- Google continues to make privacy difficult in Chromium and there is only so much that Chromium-based browsers can do to stop that. The future looks even bleaker as it relates to Chromium with Google’s upcoming changes there.
If you want the specifics behind that, read the 600+ posts in topic linked above.
To be very clear, I am not pro-Firefox. It is simply that the current situation for browsers is not a good one. The only fully featured browsers available for Linux are either based on Firefox or Chromium. 
It really isn’t the same at all. I am talking about the eco-system more broadly(all browsers based on Firefox) and a narrow part of the feature-set(privacy). What would be more closely analogous is something like “if you care about high-end ray tracing performance, you need to get an nvidia-based gpu if not, there are some great options from amd”.
If I had said, “Firefox is the best browser”, I can see how your analogy would apply.