They do! As long as the drive can plug into the iPhone it can at least read it. I don’t think it can write if the drive is NTFS. I have a USB C fish drive that is just as easily written to and read from on my iPhone 16 Pro Max as it is on my Galaxy S10.

iPhones have done mass storage forever but very few drives supported Lightning. They do exist though. When iPhone added USB C, they added a standard USB controller. Supports everything an Android phone does, and in theory, a PC. Never heard of either phone platform being able to burn a CD but I bet both could read from a CD-ROM disc (or DVD or Blu-ray). Hard drives, flash drives, portable SSDs and the like? No problem.