Adding your own passes was possible before (I used websites to create passes on the phone; apps existed too) however that's been a hurdle. I wonder what the security implications of this would be. Could people snatch a QR code on my paper ticket to go to a Taylor Swift's concert instead of me?
I can't speak for all things, but I found that venues will often use like a rotating QR code or rely on NFC. I'm sure if this is something like a ticket for a concert, you'll just rely on the existing pass support from whatever service you're using because it'll require something more complex.
The way I'm interpreting this is that it's a way to abstract stagnant QR or barcode passes for smaller businesses and libraries. We'll see at the WWDC though.
> Could people snatch a QR code on my paper ticket
That's a feature, not a bug. It means you can sell the ticket if you can't make it. Thankfully (/s) we have Ticketmaster with rolling codes now, so, no reselling.