Why did you buy one then? You are correct. The plateau is there and i agree.
I have also been in the Apple Store yesterday and i looked at the new phones in person for the first time (Space Gray Pro or Silver Pro looks the best btw IMO) and i came to realize that it's the same thing as the Xs / Xs Max, just with an improved camera system. Better phones yes, i mean atleast they kept the same pricing as last year, and the 11 got 50$ cheaper compared with the Xr's pricing last year.
It's just a revision of last year, an updated version. If you like them, you should get the Pro (Max) over the Xs (Max) and the 11 over the Xr. But not if you already have a Xs Max / Xr, or even X.
Well if you have the X, the Max is rather nice because of the larger screen. I know, many like smaller phones, but me? I definitely prefer the larger variant. X to Xs that's almost the same phone.
I have the 8 Plus 256 GB, my phone isn't even 1 year old. I bought it last year to replace my 3 year old 6s and i had to decide between the 8 Plus or Xr and 8 Plus won. Xr: No 3D Touch, no optical zoom, and the display is sub 1080p (but it doesn't matter because it still looks very decent. I'm impressed with Apple's 828p LCD).
I definitely want many features on my phone, which is why i got the 8 Plus last year (had a 6s before that, and a 5s before that), but i do not need the latest improvements straight-away. The biggest factor is, that the improvements have gotten minor over the last years. Especially when you consider the pricing. 11 has an OK price, and this phone is definitely a decent one and it will be more than enough for the average consumer.
All the new iPhones are nice, sure. But they don't really interest me. Especially not for that pricing of the Pro line.
Do i need the all-screen? Nope.
Do i need OLED? Nope. The 1080p LCD on the 8+ with 3D Touch, wide-color gamut and True Tone is fine and looks good.
Would i like an all-screen 6.5" phone? Yes of course. But not for that price. And my current iPhone was also very expensive and it's not even 1 year old.
A couple things i miss with my 8 Plus, like a Night Mode for the Camera. Or the Portrait Mode for the Front Facing Camera (X and Xr/11 also has that).
But other than that, i am happy with the 8 Plus. I also thought that i would value the ultra-wide angle lens more than a telephoto one now, but after playing around with the 0.5x camera yesterday i definitely like the 2x optical zoom more. I'd wish Apple would give us a 3x or 5x optical zoom lens. For me, it just makes more sense to zoom into something, rather than zooming out of something if you have an optical zoom lens.
The 8 (Plus) (or X) are still so amazing. If i had too much money laying around and i had no idea what to do with it, yes sure i would get the Pro Max. But that's not the case and i don't even care anymore.
The 8 Plus is far from being outdated, just because it has huge bezels or a home button. (Oh, and i also love the Taptic Engine of the 8 Plus, the feedback is so nice).
You have a 14-day return window, even when you already unboxed your phone. Return it. If you really like to upgrade your iPhone this year - get the 11 and be happy. I would do the same.
I am a huge fan of Apple. 6 years ago i watched my first Apple September Keynote live in 2013. I walked into the Apple Store a week later and i looked at the newly released 5s. Man, i wanted that phone. I was sold at the moment i picked it up and i held it in my hands. I got one a couple months later. Sure, they were like 649$ unlocked for the 16 GB, not 999$/1099$, and i only had an iPod touch back then (i was only 16) and i just wanted an iPhone after gaining interest in Apple and their products. But back then Apple had their magic still. Even in 2013.
And now? I leave the store and i say: "Cool phones, but nothing i need." They don't excite me anymore.