I took a look at the Michigan Central Train Station impact area with Google Earth and saw a relatively small development area with a walkable scale, but divided by two major barriers and potentially a third barrier between the impact area and the river.
I-75 cuts directly across the impact area as if it were dropped into an existing urban design. In places it is more than 1000 feet across. It is crossed by three combined auto/pedestrian bridges that do not accommodate pedestrians very well and two pedestrian bridges that are fine, but only two.
The railroad also crosscuts the impact area. It has three crossings with limited pedestrian capacity and effectively separates the area around Mexican Village from the train station even though they are a stones throw away.
While the walk from the train station to Mexican Village is feasible, in the current state it is not a pleasant walk.
Others on the blog have commented that Michigan Avenue is a substantial barrier, although I have not identified it in the figure
A third barrier does not exist yet, but could sometime in the future. The entire riverside is part of an opportunity zone and a candidate for future development. If that development restricts walking access to the river it could substantially reduce the value of properties in the impact zone.