Canada's Interac is anagolous to US' Zelle payment network (which is owned by the largest US commercial banks), while RTR is the US FedNow equivalent ("true" instant payment and settlement with broader use case support, operated as a utility by the US Federal Reserve).

https://www.redcompasslabs.com/insights/why-canada-needs-ano... was something I found via a search that explains some of the nuance without writing a new post on the topic, other citations and resources are welcome.

(it should be expected that newer, utility ran instant payment systems cannibalize existing, more expensive, lower legacy payment rails; going fast and being cheap as a utility is the innovation)