> That doesn’t solve brake and tire particles.

Regen braking means significantly less brake dust, especially at city speeds and with blended braking.

> Although…rail might solve those?

Trains still have brakes. Some can regen brake but because they usually don’t have batteries they need the rail or overhead gantry to support inputs.

But on a passenger-mile basis, I expect an electric train produces essentially no particulates compared to a car, even a light rail on tyres. I do not however have numbers.