Not all users have permission to do bulk trail reports. Bulk reports let you update the status and conditions of all the trails in a region in one fast form.
Users that have the following region permissions - add, edit, admin - for a region can do bulk trail reports for that region and beyond.
If a user is specified as an "official trail reporter" on a trail, that user also has the ability to do bulk trail reports.
If a user, however, has a 'trust score' of 2 or below, that user cannot do bulk reports, even if they meet the criteria above.