During the spring and summer, news sites buzzed with the rumor that Apple was going to release two separate iPhones. One would be cheaper, have lower performance components, be smaller, etc.
Like these Bloomberg, New York Times, and other mislead writers.

Once you view those rumors from a developer’s — or Apple’s — point of view, the idea is not feasible at all.
If the new devices had:

1. Smaller screens
That would mean that most developers would have to reposition many objects in their apps lest the apps appear scrunched up and distorted.
Imagine playing Real Racing on a device even smaller than the current iPhones. The size and screen are small enough as it is.
I will be holding the device differently, thank you.
I will be holding my device differently, thank you very much.

2. Lower performance components
Apps that took advantage of the iPhone’s processing power would need to tone down the graphics accordingly for each new model. This would create user confusion such as the below

Why can Ted’s iPhone X display this cool feature, but my iPhone X cannot?

Using two different components will require Apple to order two parts from a manufacturer, bringing up costs. If iPhone A sold better than iPhone B and the same number of iPhone As and Bs were ordered and in stock,

Uh oh...

Apple would be left with a shortage of iPhone A and warehouses of unsought iPhone Bs.

And you know how the media loves to speculate on that. Rough thought process:
Media's mind

Fewer devices shipped → Factory issues → Workers mistreated → Conflict resources → Insider Trading

The last thing Apple needs is another highly viewed article highlighting production woes.
3. New form factor
A flattened home button, “iPhone nano”, and the like. All of these outer, physical alterations will affect how users interact with their iPhone. A smaller device size would affect how users would play games and hold the phone. Developers would also be notified of such a drastic change in the product line beforehand.
Why would you make a pill shaped home button? I don’t know, the current circle works fine.

You might be thinking that this is a load of Hindsight Bias, but I kid you not, in a few months, all news sources that want coverage and viewers will start speculating on this rumor citing “people familiar with matters” or a “Chinese source”.
Just keep in mind that Apple would not do such a disservice to its developers by unveiling a device out of the blue.