What are the drivers to return damaged aircraft to service? Loss of revenue, loss of manufacturer prestige, the insurance companies who have to pay out? Higher insurance cost for this type of aircraft? A new aircraft expected to fly on for more than 25 years damaged in its first year of operation? a combination of all these probably.
A tailstrike can damage the lower rear fuselage area. Whatever caused the fire, the structural damage on the crown of the rear fuselage appears similar to that caused by a tailstrike, damaged skin and damage to the structure in the vicinity of the rear pressure bulkhead. Any repair would be accomplished to the manufacturers requirements but there is the chance that a latent failure site could be created. Returned to service the aircraft continues to fly and the repair appears fine only to suffer catastrophic failure much later.
I sincerely hope that history doesn't repeat itself because there has been precedents and I highlight two that anyone can research.
1 - JAL Flt 123 in 1985 747 bulkhead repaired only to fail about 12000 flights later.
2 - China Airlines Flt 611 747 tail section repaired only to fail 22 years later.
All humans that were involved in the repairs on these two aircraft thought they had done a good job, they wouldn't have knowingly built in a latent fault.
A repair could be done to this aircraft, it will be a logistical difficult task given it's location. Eventually the aircraft could be back in service but unless everyone is absolutely convinced history won't repeat itself, this damaged 787 should be taken out of service. The industry should take the financial hit. It costs money but technical development in aviation has never been easy and safety has to be seen to be paramount to maintain passenger confidence.