I'm surprised when people say this; it's like they haven't really seen a lot of transit stations. You're thinking that the choice is between huge, low-quality, garage mahals VS small, boring, and decent transit stations. It definitely would be a waste of money to create huge stations when they aren't needed but the issue here is that the building doesn't evoke any expression, have any interesting colours or materials, creates large blank walls, and overall doesn't provide any aesthetic value... which I believe is important for public buildings.