Have you read: Passwords are obsolete
Essentially a password-less login system is as secure as the ‘forgot your password’ process most websites use.
Also, Medium – this very platform you have authenticated yourself on – has implemented password-less authentication. As have Slack and others.
The concept itself is not inherently insecure; BUT as a completely newbie developer, it is highly possible that my implementation of it can be improved. If you learn of any improvements, I’d love to hear them.