You should get a warning when you open an email where the sender’s name matches a contact, but the email address is neither one you have seen before, nor one in your address book. (Additionally, a warning when the email it was sent from in the header doesn’t match the one in the ‘From’ field)
I’ve been getting a lot of spam lately where the name implies it’s from someone I know, but the email address it is sent from is not theirs (but is actually sent from the listed email). It implies somehow a spammer got a list of my friends’ names, possibly by crawling LinkedIn or Facebook.
And I’ve noticed over the years that a great number of spam emails have a ‘from’ field that doesn’t match up with the headers. Often these are phishing emails.