... am I the only one who figures that linting would logically be a very low priority in those circumstances?

Ahah! I worked on a project which used dotnet format in a commit hook. That was a frustrating experience, trying to rebase code.

(Unlike most formatters which are instant, dotnet format takes at least half a minute, because it performs a build just to format your code.)

My thinking is that the linter only has to operate on the code that was actually checked in. And just how many things are you checking about it, anyway?

Depends on what you're trying to achieve. Jobs like lint checks should ideally be pre-push checks so that the long process doesn't get in the way of commits. But very fast and small checks like warning about trailing whitespaces or ensuring a newline at the end of the file can be done during every commit (even if it was in jujutsu). I would rather not wait till the end to find out. And of course, there are ways to temporarily or permanently disable one or more checks when you absolutely need it.