Apple is NOT supposed to make a perfect iPhone. Like automobile manufacturers or other electronics, they need to save some stuff for next year's. Enough room for improvement to add something better for every successor.
If they gave us everything, consumers wouldn't have the urge to keep upgrading. They would be perfectly content. Consumers are like mice in a maze and they keep moving the cheese from one place to the next. Apple is just there to entice us for milking our cheddar.
I'm just waiting for more color options. I'm not in love with the two colors they have right now. I can picture the 2019 iPhone to be slightly redesigned but essentially the same look. Apple might revamp iOS that year. Six-year changes.
We are aware of Apple's patterns. They are as predictable as they come. Sony used OmniBalance design since 2013. Remember when HTC used the same design for three generations?
By 2019, the praises of the X will disappear and everyone will say Apple is lazy for using the same design for three years in a row again! Can't be short-sighted and be a prisoner of the moment. Every year has improvements. Just because it's an anniversary model doesn't mean it can't be surpassed.
4s added dual core, 7x faster GPU.
5s added Touch ID, 64-bit A7, and gold color option.
6s added double RAM, 3D Touch, and new gen Touch ID.
8 added wireless/fast charging.
^ I can imagine next year's X will get a Plus model but have a similar jump in specs from 6 to 6s. Then by 2019, it will look a little better.
3 GB RAM is laughable in this day and age. My cheaper MacBook Air has 8 GB and can audio play YouTube videos in the background while I open up another tab. Current iPhones don't even have the PiP feature or split-screen for two apps like iPad and Androids could.
Since I don't really like buying iPhones every year since I find iOS redundant, I don't mind waiting for the ones by 2019-2020. If you think iPhone X is nearly perfect especially in hardware, you have very low standards in computing. Only 3 GB of RAM isn't enough for real multi-tasking.