It didnt break out in any meaningful sense. What it did was get access to the internet. You take it as granted that there was anything meaningful there to stop it.
But heres the kicker, they have been testing these things connected to the internet anyway. What it did was get a level of access it has otherwise been granted in other simulations.
Its not exactly the same as any of the scifi AI breakout scenarios. Ultron isnt cranking out hundreds of copies of himself. The borg arent assimilating people.
A tool that has the capability to get access to the internet, was put into a guided scenario where it achieved that objective. Again you take it as granted that it wasnt the objective, but lots of knowledgable people suspect otherwise.
What you fail to demonstrate is why any scifi scenario is even slightly plausible from here. Show why you think we should be taking this as if Terminator 2 is happening right now.