But it is 490km by car

Sure, but the train doesn't travel by car. 396 km.

I don't get where you're going. Your initial take is that your ICE route in Germany was slow. Indeed because Germany has not a lot of dedicated high speed train track and it has a lot of stops. That is why the TGV example is brought up, as it runs on dedicated track. 1h45min for 400km (500km by road) from city centre to city center is unbeatable, and you just need to show up 5 min before train departure. That is why there is no flights from Strasbourg to Paris anymore.

The train track is 493 km long: https://en.m.wikipedia.org/wiki/Paris-Est%E2%80%93Strasbourg...

This is the old track, with normal train (around 130kmh). The TGV track is 406km and has just a few stops: https://en.m.wikipedia.org/wiki/LGV_Est