A point of contention as someone who uses write blockers and forensic tools... write blockers protect the connection of dumb storage to a computer but a phone is not a dumb storage device (it's not a SATA drive), it's actually a full device which manages it's own storage.

For mobile forensics, it's actually done through the built-in backup systems included in each of the major OS providers (Android/iOS).

This is a back and forth that has been ongoing since we began moving away from Hard Disks, as SSDs tend to manage their own internal state so an image of "an SSD" can change even if the underlying media hasn't changed as the SSD cell balancing can actually shift around deleted data or delay to clear certain cells.