In the 1990s the RPA proposed reviving an abandoned rail line connecting Brooklyn, Queens and the Bronx into the Triboro X line as a supplementary arc. The truth is the boroughs were well connected. In the postwar era the many of light-rail lines connecting Brooklyn and Queens were demolished. As were three elevated lines in Brooklyn/Queens and four elevated lines in Manhattan.

The MTA still has a gap in the funding for the 2020-2024 capital plan due to Andrew Cuomo's raiding and Kathy Hochul's incompetence, so I wouldn't expect much from the 2025-2029 capital program! It is $48 billion short of maintaining existing levels of service, "with a focus on areas in need of urgent investment".