If you beed to be on time, national flights with Lufthansa for me are close to 100% reliable whereas Deutsche Bahn turned out to be a catastrophe in about 50% of the cases. I still don’t get it: they own the complete network, they control every train on it and arriving on time at a place is like playing roulette. Neither air travel nor traveling by car gives those headaches (especially when you listen to your dynamic GPS that routes around traffic jams).
You can reduce the bad luck a bit by planning longer stops when changing trains, still making pauses longer reduces the attractiveness of trains even more.
Personally, I love taking trains when it works. It is comfortable, fast and you arrive in city centers. Even first class tickets have acceptable prices. But as I usually don’t travel for pleasure, but for business and don’t want to waste my time, German trains have become a no-go for me.
Lufthansa rarely gets "Personenschaden" ("injury to persons", an euphemism for "suicide") on their flight paths while Deutsche Bahn has frequently to deal with that. A delayed intercity express train definitely delays departure of other trains that are considered Anschluss(züge) ("connecting trains"). It then ripples through the network.
Having travel a few times TGV trains across france, while connecting to Switzerland, Belgium and Germany, I wouldn't consider them much better than German ones.
I still have a good story from a TGV travel from Paris back to Geneva that took the double of the time, partial return travel back to Paris, again reversed mid-way back to Geneva, being blocked on a trainstation on the middle of nowhere waiting for restaurant wagon supplies trying to calm down everyone, and finally arriving into Geneva several hours later than expected.
I cut lots of details on that reliable train trip.
Mostly by spending more money. Especially France and Japan built special rails only to be used by high speed trains. While those exist in Germany, there are less of them and they mostly don't reach from station to station but instead near the city centers high speed trains share rails with slower trains.
I like the „nightjets“ where you can sleep and wakeup in another city. Used that a few times.
I have to say, that if I have to be on time somewhere I take the car. DB is too much risk to miss the connecting train and the employees just look at you „well, bad luck. Next train 2h“
When I m on vacation i would file that under „experience“ and would just sit somewhere and sip coffee.
