Just wondering if anyone has tied a spinnerbait skirt out of title material, and how did it look/work/durability...

You have way, way too much time on your hands my man..they’re 5 bucks 

I used to tie flies using it, but currently I just use Flash-a-bou. It has numerous marketing names, but I think it is very similar (if not identical) to tinsel. It is very common for fly tiers. It does not have the "body" of silicone or rubber, but it has good action, is inexpensive, is durable, and comes in a host of colors. I should mention these are standard colors, not bass fisherman colors, which is a different spectrum completely.

When I use it on jigs, I lash it to the hook, so it is not interchangeable between baits.

And it catches fish! I took a 22" Rainbow a few years ago, on a pattern I call a "Shiny Thing", which is completely tied with tinsel.

Back in the 90's early part of the ought 2000's it was common to see a couple of strands tied on each side of a jig or spinnerbait.

I have some "tinsel" which was specifically marketed as spinnerbait and jig skirt material.  It would work fine and probably, actually, better for Christmas tree icicles.  It's pretty "stiff" and doesn't "undulate" so I think there are better options out there.