Something is wrong with Matchmaking
It seems as though the current new matchmaking system takes into account the alliance prestige as well when matching alliances.
What this resulted in, for this Season, is that the leaderboards are weirdly skewed to have weaker alliances ranking in Plat and higher, which was never the case since Seasons were introduced. A simple search and looking at alliance ratings vs where they rank would easily show that. (I’m seeing 6.5m alliances ranking at the top of Plat 3. And they didn’t sell champs cause their top champs are unduped 4/55s.)