[inferiorhuman]

TfL brought level 2 GoA to a few Tube lines. In the US newer subway systems are already at that level. DLR is GoA 3, and a few smaller lines in the US (e.g. Las Vegas Monorail, Miami's thing, pretty much all airport people movers) are Level 4.

[thecompilr]

Yes, newer ones don’t have the same problem, since they are not held back by the rules of a union. Sadly those are few and far between, and I haven’t heard of a new railroad line since the yet to be finished CHSR, though can’t blame that one on the unions.

[inferiorhuman]

Dude. What the fuck are you on about?

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.