What year are you playing at? I’m now in 2010, easy difficulty and some trains lose, but some earn a lot. Overall profit. No mods and no tricks in the game.
If we consider that max track speed is 300 kmh and max road speed is 100 kmh, if you carefully plan your lines (town sufficiently far apart, frequent service, etc.), trains can be more competitive in the game.
On the other hand, if you have a poor locomotive, a not very frequent service with lots of near-by stops, trains aren’t a good alternative, but that is somewhat realistic, isn’t it?