> The buildngs are drawn correctly.
That's just not true. There are many distinct buildings in these blocks. I.e. not each building is the full block width. Not to mention, this block of Laurens St currently has a large vacant piece of land near Queensberry Street.

Regarding footpaths - from the Wiki: For the best practice there is a couple options to follow, either add the tags sidewalk=left;right;both or sidewalk=separate on the same feature describing the road or create a new way marking the sidewalk that is running parallel to the road then describe it using highway=footway – see below for more details. (https://wiki.openstreetmap.org/wiki/Tag:highway%3Dfootway)