From what I’ve gathered, Ludia wanted to make it so that people always got another person to battle, whether or not the match-up made any sense at all. This effectively removed what I call “pity battles” (battles where you would fight a much weaker enemy but only gain 10 trophies for winning), which I’ve been told were actually battles against AI enemies (not real people).
The biggest problem with this is the disproportionate number of end-game players compared to beginning and mid-game players. Due to the nature of the game, there reaches a point where the majority of daily players are fighting in the end-game, meaning, anyone that isn’t end-game has fewer and fewer ‘fair’ opponents to face resulting in what we have now. This makes it more and more difficult for non-end-game players to progress, causing players to leave the game / just not battle anymore, which further exacerbates the issue.
Honestly at this point I see little hope of them ever balancing matchmaking because of the aforementioned issues and imbalance in player levels.