It isn't the train developers fault it is the route developers for creating S curve switches in actuality the train follows a straight switch path.
See below
That is why.
Its the routes not the train. So pls go.
It is exactly this. The Track makes that straight merge from 1 track to another, and the track type is invisible. The switch itself is an object. So the track makes a direct pat from 1 track to the next, while the Object shows an S curve type track. Since the train follows track and not objects, it will not make an S curve as the switch makes. To make it follow the switch, the route developer would have to make the track itself curve and make the S type curve while switching.