I'm still on iPhone X, runs super smooth. The older iPhone X runs better than my test Galaxy S20 which is newer than the iPhone X by many years.

I also have a Galaxy Edge from the same year as the iPhone X. The Samsung is completely unusable. Every tap takes seconds for anything to respond.

The accelerometer on my X finally started failing, making it impossible to hang up voice calls. It wouldn't turn the screen back on after I took the phone away from my face :-D