When trying to find genesys matches to spectate it’s often very apparent that the ratings shown in the lobby are not genesys ratings; for one, some ratings shown are higher than anyone has in Genesys, for another, an overwhelming majority of them is the baseline 100 which I find at least improbable.
I assume what’s happening is that no matter the format being played, the ratings displayed are from the Advanced TCG ladder.
Probably just an oversight, where TCG rating was the default, and it was never set up to reflect the Genesys rating instead when Genesys replaced OCG ranked.