Without the checking for trains you could set this up with a reminder with time and location (“on arrival”), once you get the reminder its no big deal to trigger the shortcut (for checking trains etc) manually I guess?
In a way you're certainly right: Not really a big deal. But then again, it's a difference like day and night. True automation versus assisted manual task-activation. I love the shortcuts feature, but not being able to have them run truly automatically (and in the background, you can't have a "wait"-action for longer than ca. 3 minutes) is a major roadblock that Apple should hopefully solve in iOS13.