It makes sense why it can't be _removed_... it's required for core OS interaction features such as a known-working login portal framework and probably tons of other 'reuse the rendering engine from the browser to display stuff' portions of the shell and settings pages.
If you wanted to de-google your phone _that_ much it probably requires a custom firmware blob that's shipped with a different browser... if that's even possible / reasonable.
If you wanted to de-google your phone _that_ much it probably requires a custom firmware blob that's shipped with a different browser... if that's even possible / reasonable.