From this thread it’s obvious most everyone wants the smallest size possible.
The few who don’t would rather go with the largest size possible and not the middle one. The ones who don’t fall in this camp, don’t want the smallest size only because they’ll miss out on essential features. So had the Pro offered a 5.4” model, they would have bought that instead of the 6.1”.
For almost nobody on this thread is price the main/only reason to go with 5.4”. It’s only the cherry on the top. You get the better sized phone. And it happens to be the cheaper one as well.
I have been saying this for ages. The iPhone 6 had the perfect dimensions. If you could make it very slightly smaller but full size, you’ve got a winner on your hand. And people will buy it regardless of how it is priced, of course within reason.
Something like the 5.4” iPhone is the perfect candidate for almost anybody coming from the SE/6-8/X/11 phone sizes. It’s what everybody has wanted all along. The only reason it won’t be the biggest success of all time is because many people also want every single feature available.
So had the iPhone and iPhone Pro both come in 5.4”, Apple would probably have got >70% of their new iPhone sales from just these two models.