I'm unsure what your experience is, but mine is in complete contradiction to this. I've taken direct trains from one end of Europe to the other. I don't know what your second map represents, but it's not direct train lines.
I've personally taken direct trains from London to Germany (some of those trains go on past Germany) and London to Italy. How they handle the electrification etc I don't know, but I've never noticed an issue or had to transfer between internationals.
Most of my train rides have been cheaper or similar price to flying once you factor in local train travel too, and exceedingly nicer and easier. You very rarely even notice crossing the borders, which is a fun aspect.
Well I don't know who the director is, nor would I have. I do realise gothic horror in general is often about sexual repression, but a lot of the film's use of it just felt unnecessary.
Maybe the intended audience are more au fait with the director, then? I'unno