[sneak]

If everyone you iMessage with has iCloud Backup still enabled (and I guarantee you 100% that they do because it is the default), then you turning yours off does nothing, as all of your conversations remain readable by Apple via the escrowed keys of the other endpoints.

iMessage is not e2ee.

[tptacek]

It does not appear to be the default.

[sneak]

Wanna bet? Perhaps I should make a video.

[modeless]

You absolutely should, I've been wondering if there was a video somewhere showing the defaults during setup.