As an example, in 2016 I took the train from New York to Montreal. The distance is only about 600 km, but the train ride took almost 12 hours! Part of that was due to the border checks of course, but even during the part in the States the train tucked along really slowly and had to stop multiple times to let cargo trains pass (which have priority over passenger trains it seems). In Europe, I also regularly took the train from Saarbrücken to Paris, which is not that different in terms of distance (around 500-550 km depending how you count) and takes just 1 hour 45 minutes.
The great thing about Switzerland is their 30 minute schedule btw: Trains are scheduled so they arrive around 5 minutes before half in all major train stations, and depart around 5 minutes after half again, so that you can hop from one train to another with less than 10 minutes delay (and trains are on time in Switzerland). They're already planning to change those intervals to 15 minutes, which would basically turn Switzerland into one giant metropolitan area, with train schedules that feel more like subway connections.