Choosing to lock things down when you're not certain of the side effects... that's the sort of thing that will, at worst, cause outages due to protocol access or authentication (which are both easily fixable). It's a smart move... and helps initiate the "Canary in the coalmine" built-in feature.

The "move fast and break things" crowd are generally the same people that will choose to open things up in the name of "getting shit done". They'll drop firewalls, expose services publicly, and generally go out of their way to avoid security because they see it as a hurdle to achieving their primary goal. In my experience, this lack of foresight almost always causes cascading problems in the future that grow exponentially worse the longer they're left unchecked.