It seems to suggest that you need to unbind whatever took that keybinding first…
Just to be sure, there is no way to globally override a keybinding (regardless what other package may later do)? I thought that SPC and M-x are somehow globally bound in the general-override-mode-map? Or can those be “hijacked”, as well?
I think I finally figured it out. This section of the guide about “evil states” explains that there “exist” (but doesn’t give an example how to override them) evil states with higher precedence that general-override-mode-map.
I recalled from the previous episode of this hell (sorry pun on doom the game, but I’m really exhausted right now) that you can add :i (insert) :v (visual) and other properties shown below* to map! macro, which might correspond to overwriting these “states”… and that seems to work.
(map! :nvi "C-<tab>" #'centaur-tabs-forward)
If we could please add an example to 1.4 in the guide that would confirm that, I think it might be helpful for future users as well.