I certainly agree about travelling faster can make things seem smaller
My interpretation of why the scaling is too small is;
- The 3d depth of the outside cockpit view is too flat and produces a very slight cross-eyed effect.. In the past, I've experimented with a pair of cameras to make 3d videos, and from what I see in Squadrons is similar to having the two cameras the wrong distance apart, and each pointing at a point either too close, or too far away (produces a similar cross-eyed feel). In itself, this can make the world "feel" smaller or larger - I've only tried this on the Oculus headsets so far. Maybe this is an issue with the game talking to Oculus headsets and other headsets are seeing it correctly.
- the rate and way the space particles move past the cockpit. Some parallax applied to the near and more distant ones would have helped with the scaling
If you park an X-wing in the trench that runs along side of the star destroyers, then turn so the nose points at top ledge, and engines point at lower edge, the x wing almost touches both ledges at the same time.
Is showing actual incorrect scale of models? From other pics and videos I've seen, the xwing would be about a 1/3rd of this size.