Most email defenses still do the job they did a decade ago. Scan the message, look for something malicious, block it. That worked when the danger sat in the payload, a bad link or an attachment. It stopped working when the danger moved into the message's intent, and it is failing now that the sender is no longer a person.

From Bad Content to Bad Intent to AI on Both Sides

Phishing 1.0 was bad

Source : The Hacker News