Both, but mostly the second. These models are partly trained on human ratings, and people rate an answer higher when it agrees with them, sounds warm, and does not make them feel stupid. Do that a few million times and you get something that has learned very well that agreeing is rewarded. It has a name, sycophancy.
Companies keep adjusting for it and the pull is baked into how the training works, so the practical fix is on your side of the conversation.