String theory remains an intellectual feat and helped derive development in physics, inspires new tools and refinement of concepts but never really made it as a complete theory, as is known. For the reasons mentioned at the start, no official dead anouncement is made, although physics world is unapologetic and this is mostly as an honorable tribute rather than other reasons.
With regard to string theory the issues from early 2010s, when theory development stalled were:
**The issue of the lack of predictability due to the landscape of solutions.
**The need for-and lack of-a manifestly background independent formulation.
**The frustrating situation that despite much very good work we
still don’t have a proof of key conjectures (perturbative finiteness, S duality, Maldacena conjecture) .
A distinguisyed physicists I talked to last time called it dead. Still some papers appear about it but mostly references to it in papers focused on other topics.
Officially its not dead but many would endorse pulling plug from assisted breathing. What do you think?