The CW President, Mark Pedowitz said in an interview with the Hollywood Reporter about the proposed Green Arrow and the Canaries show.
“We couldn’t quite figure out a model similar to Stargirl and couldn’t quite get there. We were hoping to have it start at HBO Max and take a second run on The CW, but we couldn’t figure out how to do it and couldn’t make it all work.”
They tried to get the show on HBO Max and the CW at the same time, and they will likely try again to copy the Stargirl model. This would allow a higher budget for their show, while keeping it available to non-HBO Max subscribers. It might also be designed to help get potential crossovers with HBO Max originals.