We went through the same process last spring. Our son's phone was an iPhone 7. We were able to connect it to a computer and download all his pictures, videos and music. We did have all of his passwords which we did need to get logged into the phone once connected to the computer. Once connected to the computer you had to unlock the phone with the keypad and then it was just like having another drive on the computer to copy the files from.  I would be there is a way to do it even without the passwords although it may be much harder.