Are you only imprisoning Foals or anything more dangerous then a unpowered roomba?
You must not be familiar with how durable some materials can be. 1/2” paracord and steel cabling similiar thickness is nearly indestructible. Just common rope cannot be cut very easily like you see in the movies.
Not to mention, wings are quite fragile; taking something off like this would result in wings too damaged to fly anyway. Getting anything squeezed in to tear away would cause the tensioning line to extend, activating it.
Plus there’s the potential of magically enhanced materials.
Besides, how would the pony get the necessary access to even break them? With help possibly, requiring another pony. Just keep them apart/away.
Fantastic! And I do like the Hoof Restrictors, as well, which I believe have also featured with one the previous products. Definitely looking forward to what Dagger Industries develops next!

your current filter.Edited because: had to fix my speech.