Exception being the Pixel line as Real Deal stated. I'm running Android 8.1 and Feb security update. It is as smooth as my iPhone X, sometimes smoother.
One can also argue the iPhone X has half-baked features. Face ID is not perfected yet, say what you will, it is still in beta form. It can't distinguish Asian twins (happened to my girlfriend's friend's twins 2 weeks ago, was entertaining). It can't ID you from a horizontal position. And it doesn't automatically take you to the home screen, you have to swipe.
The notch by itself is proof that the X is half baked. Apple hasn't found a way yet to pack all that power into a bezel without interfering with screen real estate. You can bet that come 2019, the notch will either be gone or drastically reduced. Likely the latter, given it is Apple.
CarPlay is also half baked. Maps is a beta as well, horrible compared to Google Maps. It hasn't worked in my car since the first iOS update after 11.0. This is what caused me to try a Pixel 2 in the first place.
Apple's OLED is half baked. It can't show notifications without waking the entire screen. Notifications in general are a joke compared to Android. There's no "always on" display like Android has done for several years. Basically they haven't done a single optimization for OLED, it is treated the same way as an LCD screen on the iPhone 8.
Living wallpapers are half baked. Whoopee, I can press on my phone screen and the image moves for 3 seconds! The Pixel's living wallpapers are great.
Again, I own the X and Pixel 2, and am having a blast with them both. Love dissecting both with people in a constructive manner over my morning coffee. As of now the Pixel 2 XL is a notch above the iPhone X.