I agree with most of what's been posted already. I'm divorced many years now and one of his things was to never have an opinion on the day-to-day stuff, leaving me almost like a parent having to decide for the two of us. (And, honestly... his input to our relationship bordered on that of a potted plant.)
BUT, then after the fact, he'd criticize my choices and when I asked him why he didn't just express an opinion to start with, he went into victim mode. Part of our problem was that he was an alcoholic and prone to revisionist histories while I was a very good enabler stepping up to the role of 'parenting' him since I came from a family that never go divorced, no. matter. what.
In the end he dumped me and that was probably one of the best things that could have ever happened to me because my up-bringing demanded that I stay with him through thick and thin, till death do us part.
NOW, as a result of that experience, I have no tolerance for people without opinions because I view them as holding that 'victim' card to play later. AND, I don't really see them as "nice" in the way you have used it. I see them as completely deceitful. Sorry, just how I view it because of my experiences.
AND... I know plenty of people who are VERY NICE and have no problem discussing/debating anything. I find those qualities (nice people + can debate topics without going for the juggler vein) some the the best people to be around. Those are the people that I see as NICE. They're people who are curious and actively seek to understand the other people that they're interacting with.