What are the consequences of not effectively managing bounced emails, and what steps can be taken to establish an efficient bounce management system?
Ghost uses Mailgun and Mailgun automatically handles them.
https://documentation.mailgun.com/en/latest/api-bounces.html
If this wasn’t happening and you continue to send a lot of mail repeatedly to addresses that bounce, service providers might limit your sending and receiving servers might block more of your mail.
Handling bounces is important.