I don't think I buy BEV trains to be honest. I'm struggling to think of a proper reason why they might be better compared to normal electric trains.

But the linked article is pretty light on info, so I'll reserve judgement till more info comes to light.

They are good for infrequently used track and places where overhead wires would be in the way, like that very Tesla employee shuttle on it's own track and container ports.

It's not the best way to go for mainline track and not suitable for long distance high speed trains.