[motorest]

> But when you're in the tens or hundreds of thousands, that's a hard no.

What? No, not at all. I worked in such a company,and oncall was indeed a thing and it was tremendously easy to deal with upstream and downstream dependencies. You have dashboards monitoring metrics emitted in calls to-from third party services and run books that made it quite clear who to call when any of the dependencies misbehaved. If anything happened, everyone was briefed and even on a call.

This boils down to ownership and accountability. It means nothing if the company had 10 or 100k employees.