Canada already has Interac e-transfer for p2p which is largely free (banks are allowed to charge, but in practice they don't charge consumers).
E-transfer was launched 17 years before Pix so it runs on email addresses as an identifier. In my experience most people use e-transfer more often than cash for person to person and many small businesses like farm stands, etc.
Interac is not settled realtime - it uses the same infrastructure that was built 50 years ago but has a more modern interface. UPI, Pix and now RTR are new settlement systems that are meant to be realtime from the get-go.