In this case it was the topic of the shaky migration story here on ActivityPub. I mentioned a currently working and effective way that works on another network (ATProto) and, as I do when this comes up, expressed my hope that ActivityPods and C2S would bring that to AP with the initiative focused on exactly that.
But silly me, I made an off-hand reference to bluesky, specifically to say it worked even if Bluesky vanished tomorrow like so many AP instances have (the topic! I kept it on topic!) or if they banned you and deleted your account on their PDS and relay.
And they did what ideologues on this topic do and screamed (paraphrasing): "Bluesky! Isn't! Decentralized!"
Which was, of course, completely irrelevant, but also a topic worth discussing with different perspectives. But off the topic, which was service-level migration strategies.
And then it turned out I had them blocked on their main for recommending mastodon dot art anyway. 