I’ve only broken out of platinum once but I’m also relatively new. I’d say ranked CAN be a good gauge of skill but it depends. If you’re just using meta decks that someone else created, the amount of skill it takes to use the deck is debatable.

I think you’d agree most of the skill in Magic is coming up with a viable deck and then climbing the ladder with it. Obviously playing does take some skill itself but the higher up the ladder you go, the more you tend to see the same handful of meta decks. So to some degree yes it does gauge skill but only to a certain extent.

It is worth playing ranked and climbing the ladder for the end of season rewards which is the main reason people play ranked from my understanding.