Yes, being concerned about putting creature habitat directly where trains run is trolling.

it's about not being stupid. You aren't gaining anything useful putting grass between the rails of a metro besides potential problems.

Someone said it's been done successfully, which is surprising if true, but it's still not really doing anything.

I didn't say there was a problem with the train lol just don't put grass on the tracks

Seems dubious, but I'm curious if animals genuinely have a comparable hit rate on regular tracks vs grass filled rails.

Saying sealed pavement is the only alternative is a false dichotomy. Off the top of my head, gravel ballast has been used for centuries.

A quick search shows 30x maintenence costs for minimal drainage benefits.

Civil engineering isn't one size fits all and I'm sure there are some climates + layouts where this makes sense. But I'd prefer putting that green space somewhere where people can use it and minimize the cost, focus and footprint of transportation infrastructure as much as possible.

But how exactly is it better? Nicer to look at maybe, but there are other materials that can provide drainage and temperature control with better durability and less maintenance.

This type of grass is native to most of Europe, to be fair. But monoculture is still not great.