Why do you think I'm switching jobs, because it is so great I can't handle being so happy at a job so I have to switch? Or maybe because it is shit. But you can't say that. I tried being honest didn't work. I tried lying, it worked very well.
Now, I don't know about you, but I'd rather not knowingly hire in this sort of toxicity. Tough love and unfiltered opinions (honesty) can simply be an excuse for being an asshole when there are other options.
The person can calmly describe that there were pre-existing problems, though, hint and be honest at them (but not dwell), and go on about how they learned some life lessons and so on. When describing the issues, use fairly neutral, non-value-based terms.
So instead of saying, "The company is shit", you can say things like, "I'm not happy at the company" or "I don't feel like i*m a good fit for the culture there". Perhaps your honesty needs help with presentation.
By the tone you write in, my guess is arrogance may have played a role when it didn’t work. But what do I know, I’m an interviewer :)