I'd like to confirm that if a retention policy is created and assigned to the entire OneDrive location, do new sites created after the policy is created inherit the policy as well? The documentation leads me to believe that this only occurs for the Exchange Mailboxes:
Like an org-wide policy, if a policy applies to any combination of entire locations, there is no limit to the number of mailboxes or sites the policy can include. For example, if a policy includes all Exchange email and all SharePoint sites, all sites and mailboxes will be included, no matter how many. And for Exchange, any new mailbox created after the policy is applied will automatically inherit the policy.
It doesn't specifically mention that new OneDrive sites will also be included. I'm hoping that this is just a mistake in my interpretation.
However, to make sure that everyone is clear, when a retention policy (or rather, a label policy containing classification labels that include retention actions) is published to OneDrive and the selection is made to publish to all sites, then new sites will get that policy. But that does not mean that labels are applied to content. It is entirely up to the user/owner to apply labels... I just want to be sure that everyone understands that no automatic application of labels happens. If you want automatic application, you need to use an auto-label policy (an E5 feature).
Yes, I'm talking about the retention policies applied as per the link in my OP and applied to locations (ie SharePoint sites, Groups, Exchange email, OneDrive accounts) for the retention and/or deletion of data.