iPhone is held together but a series of clips under the display, with its mate housed in the band. Flexing of the phone loosens the clips, causing the clicks you hear when you press on a random location on the screen. This usually occurs when the iPhone is removed from the case all the time or dropped.
If you think about it, it makes sense. My iPhone cases have always been super snug, and removing them from the phone has always been a pain in the ass.
If that would be the case you would be more concerned about the bend, because the clips have a long travel time. You would have to bend the phone to the point where the screen is actually separating from the frame.
This was a problem with the 6 series, the softer aluminium and there was no adhesive, just clips and the 2 screws holding the display.
Most people hear clicks when tapping on the Apple logo. That is where the edge of the wireless charging coil is and it is only glued to the frame there, this adhesive is unlikely, but can separate from pressure. Also, directly above it, there is the adhesive strip for the battery. The battery adhesive is a lot higher possibility for this clicking sound, as it is a bigger strip and more prone to separate.
In my case, the adhesive strip under the lightning flex cable is popping.
In any case, if you have a clicking phone because of the clips, you would see a gap between the frame and the display assembly. The adhesive that is holding the display is strong, I heat it to 80C, then I can slice it through.