Being annoyed is fine but I would argue that they should deal with it if they’re going to make me waste half the interview time sitting around.

I’ll admit to a bit of douchiness on my end but I think they should have understood the snarkiness in this situation if they value directness.

Fair enough. I wasn't there and this probably depends a lot on your tone and general vibe, the dynamic between you and the interviewer up until then, and so on. I do think it's almost always a risky move, but I think I assumed too much and I apologise for that.