It surely would improve the cities and the neighborhoods it would pass through. There was decade plus long planning process that involved master planning with the neighborhoods affected including residential and commercial development. It’s heartbreaking to look at these plans and see what could have been. There is also plenty of research out there on the positive ROI of transit on cities, and I believe the plans for the Red Line included plenty of data and justification on this matter (Hogan’s people didn’t bother to read the plan). I think the Red Line was also based on one of the lines from the mid-20th century plan to build a metro transit network in Baltimore akin to Washington DC.