Railroad deaths and injuries per capita are much lower than in the USA. I'd say the unions and RAIB have done a pretty good job at improving safety standards.
BART and Muni are both union shops. I don't know if SMART is but it postdates the HSR proposals.
As someone who lived through Muni's transition to SelTrac (the system that underpins DLR and I think some of the Tube lines) I can say the union was not the problem. The technology was unreliable and eventually abandoned by Alcatel/Thales. GoA 4 stuff is only viable along small, low ridership stretches of track. If you knock the level of automation down a peg or two it's a lot easier to scale up to busier/larger systems.