You're gonna need a lot more money than that when ~40% of MTA total spending goes to pay pensions and healthcare for people that don't even work anymore by ~2040.
You need ~35% just to keep the system running functioning (which does not include operations - like the actual drivers).
That's only going to leave you ~25% leftover for everything else - and a non-trivial percentage of that comes from the Federal Government - which may not be there in the future (when all of their money is going to pensions and healthcare).
It should be noted that the MTA has made at least some pension reforms so that current and future employees won't be as costly. Employee contributions are increased as well as the retirement age.
You need ~35% just to keep the system running functioning (which does not include operations - like the actual drivers).
That's only going to leave you ~25% leftover for everything else - and a non-trivial percentage of that comes from the Federal Government - which may not be there in the future (when all of their money is going to pensions and healthcare).