I remember reading somewhere that New York wasn't really on board with the USBRS, because they'd already laid out a network of cycling routes. Obviously NY doesn't want to expend any effort to replicate work they've already done, and as a taxpayer I appreciate that. Duplicate signage isn't needed, for sure.
In fact, you could use NY B 517 and B 5 to implement USBRS 30, NY B 9 to implement USBRS 9, and NY B 14 appears to go where the AC map puts USBRS 15. This certainly counts as cycle route miles implemented, even though it doesn't go by the US routing names.
Is AC considering somehow referring to New York's existing route system? This could also go the other way too, if NY DOT were to include references to the USBRS on their interactive map or next printing of paper maps. Does the same situation come up in other states that have a route network, such as Pennsylvania?