Beginner here interested in recreating this sign. Would I just apply a physics collision modifier to a bunch of squares and use the wind force field to recreate the flickering effect of the sequins?
I don't know if this will work for you, but give it a try. Make 2 planes - Subdivide one by 30 or so, and scale the other down (I scaled by 0.1, then 0.25 again to make it "small enough" - you will be able to tell if there's any overlap in the next step)
Add a Geometry Nodes Modifier to the large plane, and instance the smaller plane at each of its vertices by using the node setup below. For the Attribute Randomize Node, set the Attribute to Rotation to affect the rotation of each individual instance.
To animate the "wall of squares", add a Value Node set to #frame (just type it in the box) and maybe use a math node (Multiply by 0.5 or so) to slow things down. Connect this to the Seed input of the Attribute Randomize:
The movement is a bit choppy (due to only changing the seed value), however it still seems to replicate the video convincingly. If needed , there are further steps that can be taken to restrict the rotation of the squares to the X-axis.