Copy Transform constraint
Using a copy transform (or copy rotation and or scale) from target space local with parent to owner space local for each descendant targeting a common ancestor bone will achieve this
Add constraint to one bone select all others and Bone > Constraints > Copy Active to Selected so its pretty easy to set up.
Will also ...
Using "child of" constraint:
Add the constraint to each of the bones, using "set inverse", relatively to its parent:
Tune the influence to be progressively decreased: 100% for the first then 75, 50 and 25 (as 4 bones in my example).
-will work under some limits, because if too much rotation the last bones will turn over the ...
The easiest way to do this effect is to animate the Y offset in sync with the bottom crop.
So enable Crop and Offset and insert a keyframe with 0 value for Offset > Position Y, Crop Top and Crop Bottom where you want the animation to start.
Divide your video's height by 2 then go to the frame when you want the animation to finish and insert a keyframe at ...
After viewing your model, here's what I did:
#select the meshes then ctrl+A to apply all transformation.
#select the object go to edit mode and select all the vertex by pressing A once or twice. And then shift+N to recalculate normals.
Your mesh had some flipped normals which caused the issue you marked. Here's the File after applying the fixes I mentioned.
Thanks to moonboots comment, looking up proportional editing and uv map made me find the video that introduced the technique I was talking about: https://www.youtube.com/watch?v=SXyIhYcYmoo
Turns out I needed to have Live Unwrap checked and transform my pinned vertices on the EDGES of my unwrapped mesh.
It seems that applying this solution will work. However, I had to make a global collection for all my pieces (as I had multiple separated walls breaking), so I could make Select Objects from all the pieces and could remove Rigid Body (Object > Rigid Body > Remove) from all at once. Otherwise, only one of the walls would remain and the others would ...