Operational emails ignore Unsubscribed and Marketing Suspended statuss. They send no matter what - Make an Email Operational - Marketo Docs - Product Documentation
Besides, setting an email to operational removes the unsubscribe link from footer as well. These are meant to be sent only for situations where recipient cannot consider the email as unsolicited commercial email (Spam) - Learn more
If we want to send a white-listing email (first and last attempt) to unsubscribed leads as well, is there any other way to send them this email, except setting it up as operational? Would this email count as commercial email? One way could be using a custom link added to email to unsubscribe, however - If we consider the leads to be opted-out/unsubscribed unless they opt-in via the white-listing email, does it actually makes sense that unsubscribed link in footer is removed?
Looking for thoughts on this!
Operational emails will be removed the unsubscribe link only if you are using the Marketo default unsubscribe link settings.
I recommend using a custom unsubscribe link and manage it through dedicated modules and snippets in emails, so that you get all the flexibility you really need.