You miss the point that the measured time and distance for the voyage of the spaceship depends on what frame is doing the measuring. In the Earth frame, of course the distance is 7 light years and the travel time is a bit greater than 7 years. But in the spaceship frame, the time and the distance are quite different.See, now that is why I can't understand the general scientific acceptance of this area.
If the destination is seven light years away from Earth, i.e. it takes light severn years to reach us from there, the speed of light is constant etc. then we can calculate the physical distance between the Earth and this destination.
If a spaceship is travelling to this destination it still has to travel that same physical distance irrespective of its speed. How can it do anything other? If the distance is the same and the speed of light is constant, then how can the time taken be anything other than seven years...?