What's next is to try taking a good phone of same make, model and revision then having a tech move the memory and CPU from the dead phone to the new phone. This is advanced work which I posted about such a service for Apple phones. This is not me making this up. You have to find a similar tech and company in your locale.

Read my example at https://www.cnet.com/forums/discussions/apple-iphone-data-recovery-extreme-conditions/

This can be very expensive work as you need the donor phone, the new phone and hundreds of dollars for the tech workers. After folk experience this they suddenly understand why backup is cheaper than recovery.