Make allow-links-change-zoom false by default
Since there is no GUI for this (except for dconf-editor) it would be a more sensible default to avoid breaking the reasonable expectation that zoom level will be kept as set by the user after clicking a link or navigating from the TOC.
I see no reason for the current behavior, maybe some excessive concern about missing some part of the target page if zoom to fit is not done after jumping, which compared to the constant annoyance of having to manually refit to width after each jump will only pay if, at some moment, that missing part were about surviving the zombie apocalypse happening at my door :).