I cannot speak for BART, but in NYC the MTA has been trying to automate its trains for many years (since the early 90s for the latest effort) and has only barely been able to keep everything working on the one line chosen for the pilot program -- and that is one of the simpler routes in the system. While I am sure that automation is possible and that the technology is available, the MTA seems to be making all the wrong choices, and I would prefer to have human operators until some minimum technical competency can be established (we can start with this: trains that can reliably announce their position on the line, without needing a human being to set things up -- one would think this is a bare minimum for automated service).
So ... lots of people have a financial stake in automated trains not working, and for some reason MTA is moving in a direction that consistently doesn't work. Quite a coincidence there.
It is a coincidence only. The MTA has been engaged in various labor-reduction initiatives and has been steadily reducing the size of its workforce for years. Beyond automated trains, the MTA has been building "master towers" (with a long term goal of having a single control center for the whole system), repeatedly trying to remove the need for conductors (and then being told by the fire department that one man is not enough to evacuate a train quickly enough), removing token booths, etc. The real pattern with the MTA is hiring incompetent engineers, particularly software engineers -- their payroll system is in a miserable state, they have yet to computerize their system for recording when trains arrive in stations, bus stops still lack information about when the next bus will arrive or even where that bus is, and the attempt to modernize their communications system went bust in just one day, leaving everyone running back to their older office (across the city) just to handle the radio traffic. You might say that there are financial interests in holding back some of these projects, but for the most part the MTA's M.O. is to hire contractors who fail to deliver, then pay them more to continue to fail to deliver, and then abandon the project and hire the same contractors to fail elsewhere.
