In the thread "Proposed changes to merge request workflow" I agree with Matt
that expecting a contributor to find reviewers will not work.
I'm wondering if we implemented code ownership better it would somewhat help
with the problem. If we had at least one responsive owner for every file then
a reviewer would be automatically assigned to every MR, solving the problem.
You may say that we simply don't have enough people to assign one responsive
person to every file, but that's a problem that a new contributor won't be able
to solve anyway, so this is not a disadvantage over the proposed plan.