Yeah, I asked myself the "friction question" too.
As a developer I was a big proponent of 'magic link' style authentication when it was new.
As a user who occasionally runs into this now, I hate it.
Why? I never run into it. I quite like the infinite login sessions, of course, so assuming the only friction is when those expire?
It’s annoying AF for me - I can 1Password into a site with incredibly secure password instantly - but with a magic link I have to find my email client, wait for the email, click it, etc. as a sign in backup it’s nice but as the Main signup it’s a pisser.
I once implemented a non standard signin where all that was needed was an email link which kept you signed in.
Users hated it.
They actually went to the trouble of complaining and no doubt it lost me potential signups.
These days I only ever do normal email and password signup.