I think it's been more than 1 year now that ELO matchmaking was introduced.
However, the whole ranking system makes no sense at all. You could have the highest ELO in the game, but be in gold rank or even stone, just because you've been inactive.
Even after 1 year, I see people complaining that they get matched against people of a much higher rank, or that they're in master rank and got a gold teammates, and such things.
People in 2v2 randoms gotta be like: "omg, a gold teammates, and I'm up against 2 master players. I'll just go AFK, can't win with this noob. bs game."
People in premade gotta be like: "what?? master opponents when we are in plat5?? great matchmaking, bs game."
If they would see the ELO numbers, they'd know their opponents are on the same level, but with the system as it is right now, they're frustrated.
Lots of people still don't know that the matchmaking is ELO based, they'll never know, and some even don't wanna know, or don't believe it, and I can't blame them, because the only way to figure this out is to be active in the discord or chats.
One would expect that the ELO represents your rank, but as we know, we gotta grind until our rank represents our ELO.
It also always makes high ELO players look very bad when you play premade with someone, and suddenly you only lose because now you and your premade partner face hard opponents, when the partner was previously only facing bots.
With the current system we have absolutely no feedback about our opponents. Did I just lose against a really bad player, and have to improve my deck and gameplay? Or did I just lose against a very good player? Who was that guy in gold5, a top player who just hasn't played MM or this game mode for a while, or was it actually a new player? You get what I mean. Show ELO ingame, it's overdue.