> A delay of two seconds in my commit hook pushes my blood to the hydraulic pressure of a 70-ton digger.

Why though? Surely you have it set up to lint as you edit? I know my neovim installation does that and I see the results in the editor as I type.

If it's a rule that linting needs to be in the commit hook, maybe the linter should write a hash of the files linted somewhere. The commit hook script then only lints those files that have changed since the last lint took place.