> Do you mean generally, or by default

We don't have to change the existing behavior if there are concerns about
backwards compatibility. But it is a common situation where you want to
define bindings in a minor mode, but you don't want them to override
minibuffer bindings. This often comes up in completion packages such as
https://github.com/raxod502/selectrum, and there is no existing solution in
Emacs---all the options are more or less hacks. If there were a way to make
this happen, then it would be a great improvement, even if it weren't the
default.

I can indeed think of situations where you want to override a binding
globally, so it seems like it would be best if there were ways to declare
this behavior on a per-mode basis.