Is it the 1" smaller screen that is highly desirable or the thick bezels surrounding it? Or perhaps it is the milky grey blacks of an edge lit LCD display). If portability is such a priority, wouldn't an MBA be better? Perhaps its not the portability that is appealing but the Touch Bar. I know some people like it. Maybe the 13" MBP appeals to people that don't like ports on their laptop (perhaps some of the same people who wish for the return of the 12" MacBook).You're making the common mistake or projecting your wants and needs to everyone else and then declaring it's "overpriced" just because you personally don't see the value for you. For many people, that 1" smaller screen is highly desirable for portability, just like you hear people saying they wish they would bring back the 12" MB even though we have 13" MBA and MBP.
In all seriousness though the 13 does have one advantage over the 14" MBP and the MBA, the battery life is quite good. That doesn't mean its not overpriced. The Magic Keyboard on my 12.9" iPad Pro is overpriced but I bought it anyway because a better alternative does not exist. I still think it is overpriced.