Nope, it is perfect for me. I am coming from a 5s; I waited a long time to upgrade as I wanted a larger screen but the 6/7/8 screen was not quite “enough” for me, and while the screen on the 6+/7+/8+ was a great size...the body was absolutely not great for my smaller hands and tiny shallow lady-pant pockets. The width of the Plus was the big deal breaker as I could barely hold it with one hand, never mind really “use” it one handed. I tried so many times in store and with friends phones to “love it” but could not! I still will mostly be typing two handed on the X, because small hands and short thumbs, but I can do a lot one handed (gestures, scrolling, basic browsing) I could not on Plus without risking dropping it.
I use my phone a lot too for work out of the office, and find this is a great balance of screen size and actual form for me, personally.
Do not miss having a home button at all, it feels very natural to just swipe up. FaceID has been great for me so far but the real clincher was when Face ID worked this morning in the dark as I fumbled for my phone on my nightstand.
I am not sure why some are having issues with Reachability, though? I have barely ever used it before (just those times I tested Pluses) but I have had no issues with it or the gestures to activate it. Just a quick swipe down a little above the bar and there it is (assuming you enabled it).
Anyway, I am not sure the X was ever meant to replace the Plus for those who like that wider screen and features. It is rather for those who wanted a phone fairly similar in size to the regular 6/7/8 (for portability, comfort, etc) but a bigger screen. And who were ready to adopt to things like FaceID. If you really love the more tablet like features of the Plus (from size to apps) then yeah, you might not like the change to the X.