Arguing that a cell phone is nothing more than a set of pants pockets is deliberately understating the reality in order to justify skirting the Fourth Amendment.
The argument is that because a cellphone is in a person’s pocket, it is fine to search the contents of the cellphone if you already are searching the pants. Which is stupid and has been shut down twice, though Texas is trying a third time.
Personally I think the smart move is for cellphones to delete after just three bad pass code unlocks instead of ten. Then I could let the police delete the contents by telling them the wrong code just three times.