I had a hiring manager ask me this and she didn’t like my answer. I told her that I didn’t wish to be negative and that I overwhelming found it a positive experience. She wouldn’t let it go.

She spent about 10 minutes asking in different ways what I didn’t like about the company. I knew why she was doing it but I wasn’t going to give her the information she wanted. She shared that the company I worked for her company had also done consulting. I know, because they replaced me. However they replaced them she told me, and her questions were designed to find a way to regain them as a client not because she was concerned if I was being fairly treated.
Many times as an ex-employee third parties will ask you what you know as a way to get a leg up into selling for them. I have been offered hundreds of dollars to take surveys, give feedback, and talk about specific companies. I don’t do it. I will talk about companies in general, but I am not going to give away the secrets of a company just because I no longer work for them. This isn’t to praise me but rather to say that I respect those I have worked for, even when they have done illegal things.
Most companies I have worked for have been amoral. They haven’t cared about the law or ethics or respecting others. I accept that that is what they feel they need to do to survive. I can’t change someone else, I just have to know what are my limits and when I reach them then I push back and have to find a more ethical place.
I didn’t get the job with the hiring manager who was pushing me to spill negative things about the company. I don’t want a job if I have to feel icky to get it. I don’t want a job if I feel too icky to keep it. And I don’t want a job if they tell me that it is going to get ickier in the future.