Chainmail provides little to no protection against impact damage. As we saw in Fellowship, evil beings who attack heroes in bed use slashing attacks with broadswords or similar weapons. While it might prevent cuts, it’s basically like being beaten with an iron rod that will break bones and rupture organs. It is unsuitable as armor. That’s leaving aside weapons like maces, hammers, and clubs, or a Seal Team Six scenario.
It’s aluminum. Or aluminium, if you’re that kind of person. This is basically a blanket designed by Jony Ive. It doesn’t warm. It doesn’t protect. But it’s thin and lightweight. Which is the opposite of what you want in a weighted blanket.
You can buy weighted blankets that come in a variety of weights and warmth characteristics for a fraction of the time investment used to make this. The money you save could be used to buy a home security system that includes a minefield or electric fence. If you’re impressed by what a claymore sword can do to an orc, wait until you see what a claymore mine can do.