An autonomous team that does what they are told or an autonomous team is free to pursue opportunities as they see fit are both useful and can react quickly. The question is how much scaled alignment you need to execute a particular goal.
You can’t invade a country with one squad of 10,000 soldiers or 1,000 squads of 10 that do as they please. You need to delegate execution authority to small teams who are aligned to a shared goal.
Similarly, you can’t expect one group 10,000 devs with no internal structure to explore and find interesting opportunities to explore; you’ll just get noise. Nor can you try to manage 10,000 devs directly. You won’t be able to grok the context.
Complexity management in organizations follows the same patterns as in code. Single responsibility, don’t repeat yourself too much, encapsulation, etc.
It’s really a function of information theory, the more people you have to ramp up or keep current on context, the lower your ability to make and stick to decisions.