Counterpoint to your counterpoint: The NYC Metro is actually 4 or 5 separate rail systems, all formerly private companies that went bankrupt. The MTA was created to salvage those rail lines in the face of private failure.
It's FUD that the MTA Union has prevented "any sort of automation...etc" because it's simply not true. They've resisted specific types of automation while supporting other types.
Changes were never implemented because the system lacked sufficient funding--it's controlled by the NY state government, not NYC itself. Most of the state is actually extremely conservative compared to NYC and generally resists implementing improvements to the MTA.