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Works for modern trains, too. I was watching one of the new electric CALTRAIN multiple units pull into a station. The motors did all the braking except for the last few feet of stopping. The friction brakes normally go on below 5 MPH, and are rather noisy for disk brakes. Emergency braking is friction brakes only.

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The brake dust from low-noise train brakes smells so incredibly nasty (burning ABS, pretty much) but the operators and OEMs claim it’s <<safe>>. Bonus points for the Bombardier bi-level coaches, where the AC air intake is right above the wheelsets and takes a healthy gulp of that brake dust and smell and distributes it to the passengers inside (because the smell is just as pungent inside as outside a few seconds after coming to a stop I doubt the filters, if any, are doing much). Frankly I’d not commute with it.

Filters catch particulates, but not gases. Heated ABS releases chemicals like 1,3-Butadiene, a small molecule (4 carbons), gaseous at room temperature, and mildly gasoline-smelling. It's bad for you in high concentrations.

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