Downgrading as a well-managed process is not a popular concept on any platform. Even fairly open ones will generally require you to fully remove the version you

Downgrading as a well-managed process is not a popular concept on any platform. Even fairly open ones will generally require you to fully remove the version you have, find an older download file, and install it. And unless you have backups, good luck downgrading your data files back to the older schema. I imagine a well-managed downgrading system would discourage malicious use of auto updates, developers would need to woo users into continuing to move forward.