I don't know about the question being a trap. If you don't try to be too sly about it, you might even turn it into a plus for you. If it were me interviewing, my biggest concern would be that the OP is burned out, and thinks that working at a startup will be nothing but sunshine and lollipops.

Instead try being a bit more concrete: "I didn't like BigCo because of <specific, observable and especially non-judgemental facts go here>. Some people like that, but that's just not what I enjoy. I'm curious to hear if you feel I'll run into the same problem working for you."

If a candidate said that, I'd be more convinced that:

1. The candidate is willing to leave the BigCo world behind.

2. The candidate has realistic expectations of what a startup will be like.