This thread really became an Android vs Apple thread LOL.
It really depends on what you are upgrading and what you are using.
I'm deep into the Apple ecosystem so I always buy their new products (Computer, Phone, Tablets,...)
It's easier for me, everything works together, even on cars with apple carplay.
I also really love their interface and stuff and I really do not enjoy Androids but that's just me.
Now, if you clearly want an iPhone and you don't know which one to choose, the iPhone X is still a nice phone. It's last year model so it's clearly not obsolete yet.