Are you sure they are just pressing?
Normally swiping down form the top left corner will bring up notification center which shows the time prominently with notifications under it.
Swiping down from the top right corner on an iPhone 11 will bring down Control Center which does show the carrier and signal a bit larger along with a bunch of other controls.
On an iPhone 7 swiping down from any point at the top will bring down Notification Center.
Control Center is accessed by swiping up from the bottom of the screen.
Use notifications on your iPhone, iPad, and iPod touch - Apple Support
Use and customize Control Center on iPhone - Apple Support