The base variants of iPhones are very popular among people, especially during sales. Many people buy and use vanilla variants to experience full-fledged iOS, cameras, etc. But the last couple of years hasn't been that good for Apple, especially for base iPhones. iPhone 14 is one of the least-sold iPhones in the last decade, and there is a reason.

The main reason for this is the fact that iPhone 14 is iPhone 13 with the same chipset, same design, same display, as well as same storage.

The minor changes in iPhone 14 from iPhone 13 include the usage of the 12MP sensor from the 13 Pro, a slightly bigger battery, one extra core in GPU, Autofocus in the front camera, satellite calling (selected countries), and crash detection. All of these are for a USD 100 price increase.

The upcoming iPhone 15 has some better changes including the usage of the next-gen chipset, Dynamic Island, a 48MP main sensor from the 14 Pro, etc.
Unfortunately for most, the iPhone 15 is still stuck on 60hz in 2023. Surely, they will offer 120hz on their base variants, which they sell for $799 USD.
iPhone 13, 14 & 15
— Anthony (@TheGalox_) May 28, 2023
It's impressive how much iPhones have changed in three years pic.twitter.com/VWcBUCsZ8S
The new strategy of Apple to keep the upgrades in vanilla variants limited to boost sales of Pro variants may work for a while, but in the long run, this could hurt them.