Well sure, but access to that compute is gated by simple credentials (like API tokens). Those can be hacked.

Imagine for example if a model hacks into ~every Linux computer on the internet using an 0day and steals their OpenAI, anthropic and openrouter credentials. It now has access to billions of compute and the only way to fully stop that is for multiple major providers to shut down services entirely. That's already well into "billions of dollars of damage" territory.