76 hours in. I stumbled on a place called "General Atomics Galleria" on my question to unlock every map marker. The guide pointed out that the characters there were supposed to be friendly, but for whatever reason only 1 Mister Handy was friendly so I had to cut them all down (and the friendly one turned hostile when Ada thought friendly fire would be fun during a live-fire demonstration of the Mister Gutsy range).
It was too late when I realised there was a terminal to reset all the bots and make them friendly; I'd already cut them to metal scraps. Reading through multiple forums and the Wikia page, apparently the instant-hostility is actually a bug which can be caused by use of the Targeting HUD, but I haven't had that on any of my gear for many, many hours, and certainly nowhere near these bots. It's possible that Ada triggered a fight when we arrived and they all got triggered, but I'm not 100%.
EDIT: Ada has become an ultimate anti-son-of-a-bitch machine, but because she has Sentry Bot legs/wheels, she frequently gets stuck in all kinds of geometry and even launches herself/other characters into space. Thanks to her rockets and the "blue spiral of pissing off people", she frequently hits friendlies and gets me in trouble. But gosh darn is she one hell of a saviour for taking out Deathclaws and also carrying lots of weight.