This is because Apple displays the battery icon and the text for the current battery percentage as two separate objects. Instead, Apple chose tocell phoneSpace is reserved for signal information and Wi-Fi connection.
The percentage is now represented as a number inside the battery indicator. This saves space while keeping numbers readable in small icons.
The feature first appeared in iOS 16 beta 5. It’s unclear if this represents a final release, or if the feature will eventually be phased out.
Apple is expected in the new “iPhoneThe 14” is followed by iOS 16 in September, and before that, expect more beta builds and tweaks to new software features.