Legend players in noob brackets?

I am a new player to the game. I’m only silver 7, however, I’m routinely being put up against players who have their legend card back, - even the year of the scarab one. I’m also facing decks that are filled to the brim of signature cards, diamond cards, and golden cards. What is going on with the matchmaking system when I as a new player am being put up against obvious pro players in the noob bracket of silver 7, consistently?