I'm going to call bullshit on his definition of this as being the first ever suburb. He defines it just such so that it fits his narrative but if we define a suburb as a mostly "outlying district of a city, especially a residential one". Then suburbs are just about as old as large cities.

Take ancient Rome for example. The formal city of the Republic was built inside the Servian wall, but what were essentially suburbs formed rapidly outside this boundary and spread widely, with residential and commercial districts. The later Aurelian wall covered these too, but again, further suburbs spread beyond that as well.

The article loosely argues that suburbs are defined as being planned outlying communities with middle class populations, but for one thing, this isn't a hard definition of them and secondly, such things also were the case as far back as antiquity.

Going back to the Rome example, many reasonably well-off people moved outside the city walls precisely to escape the dirty clog of the core, and even planned suburban industrial/business zones were created there. An example of these: the immense (even by modern standards) state/business-controlled Horrea Galbae warehouses for imported goods, well outside the older Servian walls of the city.

There's just no way I can think of defining such urban spread as anything but suburban growth, far, far before the 19th century.

edit: Just for a visual idea of what this Roman suburban district and those giant warehouses looked like, this image is a decent example. They were well outside the main urban area and truly were enormous, with well over 200,000 square feet of floor space, all inside a single massive building. http://www.galba.net/horrea_galbae.html