The CW has yet to release a statement as to why they decided to pass on this series.
Arrow helped to build this enormous universe of interconnected shows over its eight-year run, and set up stories for Laurel Lance, Mia Queen, and Dinah Drake, among other characters that were close to Oliver Queen in the series.
The Hollywood Reporter revealed that The CW has passed on a potential Arrow spin-off show entitled Green Arrow and The Canaries. This series would have seen Katherine McNamara, Katie Cassidy, and Juliana Harkavy reprise their roles as Mia Queen, Laurel Lance, and Dinah Drake respectively
After nearly a decade of storytelling, so many of these shows are now coming to a close, which certainly seems to indicate that it may be only a matter of time before the Arrowverse finally concludes