Bletchleyite
Veteran Member
It’s basically as we have yet to invent a word for “S-Bahn” (and of course because we don’t use the word Metro for either of our 2 urban underground systems- Tyne & Wear being more S-Bahn)
Merseyrail does seem to be transitioning to the Metro brand, though it is really an S-Bahn I guess (though with rolling stock derived from that of the Berlin U-Bahn I think things are now rather blurred!)