Considering how that preprint has sparked interest in other research institutions and multiplied the resources allocated to the problem, I would say this publication was not premature, it's most other research results that are late.
The paper was leaked early. The team wanted more time to get more attempts at producing it and improving their yield. The paper also wasn't generally up to their writing standards. It's essentially an early draft that was leaked.
Considering how that preprint has sparked interest in other research institutions and multiplied the resources allocated to the problem, I would say this publication was not premature, it's most other research results that are late.