First, I changed your coat tail bones from Quaternion rotation to Euler XYZ because you won't ever need quaternions if you don't also have 3-axis rotations (and you don't have them because the local Y of your coat tail bones is not of relevance to any motions). This change wasn't essential to the solution which appears below, however, so while my version of your file has this change, if you don't want it, you can safely switch the coat tail bones back to Quaternion if preferred.
Start by selecting all your coat tail bones in Pose Mode. Open the Bone Constraint tab in the Properties Panel. Uncollapse your Limit Rotation constraint listing (NOT the Copy Rotation one). Hold down the Alt key, and while it is held, change Owner from Local with Parent to Local Space. By holding Alt while doing this, it applies the change to all selected bones at once.
Your coat tails will now respect the rotation of your waist bone, but also rotate with your thigh bones.
Here's a link to a recent video I watched that I thought was very good for helping me more deeply understand how constraint space works in Blender.
Hope this helps.