The Duplex double twin home question

The type of architecture that I would like to discuss today involves the duplex. However the term duplex may not entirely describe the type of Buffalo architecture I am interested in. There is some level of discrepancy between what constitutes the duplex. For instance I live in what I considered to be a duplex however this appears to be a made up term because I could not find an appropriate listing in the architecture of Buffalo website. The closest that I could find concerns doubles. Even these doubles are not quite like the house i live in. The majority of doubles like those found on Hertel Avenue are upper and lower doubles. These type of buildings do seem to fit into the standard definition of the double, at least according to the standard of upper and lower levels comprising two separate living situations.

However this is different from the housing wherein the occupants live side by side. upon further investigation it appears as though a popular name for this type of house is a "twin home". In the neighborhood that I live there are these "twin homes" or "duplexes" if you will for blocks upon blocks. What is this an indication of? Well the website when it talks about the "industrial vernacular style" seems to point towards a definition that likens the use of these types of housing situations to working class and lower rent neighborhoods. In some ways this can be true, especially in the neighborhood that I live in. But I still find this unusual, judging from this picture of a house which is located 2 blocks from where I am, one would not, I don't think, classify this as a lower standard of living. Maybe it's just the people and places I associate with. Maybe because it looks better than my house.
When you look at something like the duplex above and this one from North Buffalo around the Colvin area

you can definitely see two distinct structures. However I, as not an architect, would see both of these as a duplex. This is how wikipedia defines duplex, "a dwelling having apartments with separate entrances for two families. This includes two-story houses having a complete apartment on each floor and also side-by-side apartments on a single lot that share a common wall.^[1] By contrast, a building comprising two attached units on two distinct properties is typically considered semi-detached or twin homes but may also be referred to as a duplex".

I believe a major part of the difference between the double of the city and the "twin house" is the amount of space available. There is a good deal less space available within city limits but once one gets to the suburbs like Amherst the amount of space increases. People no longer have to live on top of or under each other. Having lived in both types of houses I prefer 'twin homes" to doubles.  But why not have rows of single family houses in these  neighborhoods? Well the answer is one of economics. The areas of suburbs, at least in my region of Amherst, are designed for college students, and similar lower income families. However one might not think that by taking the houses in individually.

The other thing that is interesting about the "twin homes" in this neighborhood is the amount of diversity among these houses which do look quite similar at first glance. Take for instance the picture of the home with the columns. These look to me like something that wants to attempt a Greek Revival motif. The picture below it is directly across the street yet presents a very different style. Although to me the triangular arched doorway is also indicative of the Greek fashion, i.e. the Parthenon.

But then you see other houses which are completely plain, all of the ornamentals have been stripped even though one can see a facade on the front of the house. This house looks more like a tenement row house than any of the others. It feels as though the feel of the houses in this particular area were designed as row houses but later split off because of the larger amount of space involved.