Is it really good OpSec to log me out of outlook every hour when the password manager lets me automatically log back in?

Use a refresh plugin that refreshes the page using a random value between 15-25 minutes.

The random part is good because it looks like normal usage.

Seperaten processes.

Outlook logs you out so a session isn't open forever, which can have benefits in security (stressing the word can, in case of a clusterfuck of outlook ... Well. XD)

That your password manager logs you automatically in again, that's a separate process.

The login _should_ create a new session, so the state of the previous session _should_ be deleted and invalid.