Final answer:
The 'devastation of the Indies' led to increased vulnerability to exploitation by Spain's European rivals.
Step-by-step explanation:
The most accurate outcome of the 'devastation of the Indies' was increased vulnerability to exploitation by Spain's European rivals. The colonization efforts of Spain resulted in the depletion of local environments and the displacement and mistreatment of Indigenous peoples. This created opportunities for other European powers to exploit the weakened Spanish colonies and compete for control in the Americas.