$wgEnotifMinorEdits causes email notifications to never be sent for minor edits. There is no per-user override, which means it will no longer show "Email me also for minor edits of pages and files" in preferences.
$wgEnotifMinorEdits is false throughout [[ https://phabricator.wikimedia.org/diffusion/OMWC/browse/master/wmf-config/InitialiseSettings.php;fdfd3617c65fef8f9f4b2ae5e9d1fb8b442adbd8$10829 | almost all WMF wikis ]].
I think it would be more intuitive to set it true everywhere, and set $wgDefaultUserOptions['enotifminoredits'] to false in these places. (The wikis with $wgEnotifMinorEdits already true should have $wgDefaultUserOptions['enotifminoredits'] true.
The wikis with $wgEnotifMinorEdits already true should start with $wgDefaultUserOptions['enotifminoredits'] also false (since it is now), but perhaps be asked if they want it true (that would change the current behavior for them)).
That way, it would be default-unchecked, and people wouldn't get emails, but they could still choose to. It is one more preference, but it's tucked in a section with 3 checkboxes already, and I think it's a net benefit to let people choose.