Apple seems to have dropped support for Reachability feature in iPhone X, however, we will update the post if we get a confirmation. (iphonehacks.com)
If you don't use Reachability and find that it gets in your way, it's easy enough to disable. (howtogeek.com)
The center stack has been raised and brought closer to the driver to accommodate the 12 - inch Uconnect touchscreen and improve overall reachability of system controls. (iimediaevents.com)