Really?
1-2 years ago FBI wanted Apple to produce an IOS update with a back door, so they could access the iPhone of man suspected for serious crimes.
Apple refused - with the argument that such an IOS will certainly be spread and used to attack innocent people's phones. Some would say that it will certainly not happen, but the experience is that it will.
So as far as I know they didn’t succeed to open his phone.
A standard setting in an iPhone is that it deletes itself after 10 wrong passwords.
PES is right that even a delete command doesn’t destroy all data, because a memory-cell can malfunction after a number of writes, so the memory places data in different physical places instead of owerwriting. So when you rewrite a text it save the whole file in new sectors and in that way most of the file can exist in many places.
A comment to that : most ‘HardDrives‘ are not ‘old-fashioned’ magnetic disks anymore, but are digital, so if you will delete it, you will have to overwrite
all sectors with some form of noise. (Which also means that program options to ‘optimize’ a HD will not improve anything. It will only work on magnetic drives and that way place all the sectors in a file in a nice row, ready to read.
It is in fact possible to remove the chip in a memory card and read the data. But if the data is encrypted they will not succeed in that. I presume that iPhones encrypt the data, but I am not sure