Emails from all inboxes being lumped together

Within the last several days, all emails from my two email accounts are being lumped together in Apple mail. The list of emails is shown as All Inboxes, but I'm unable to find where to separate them - to view only one Inbox/email account at a time.

Is there a way to separate them out again? Sort by mailbox doesn't seem to make a difference. I'm using Apple Mail on my laptop. (Ventura 13.5.2)