Where did you find that information, Matt? The Apple official information on e.g. https://support.apple.com/en-us/HT208436 still says "The 64-bit transition for macOS and macOS apps is still underway, so final transition dates have not yet been established."

Hence I unfortunately think that that the message from June still holds: High Sierra will be the last macOS release to fully support 32-bit applications “without compromise.”

/Björn