Bias is Inevitable
You have to stop adding your own voice and take to the topic. For example, don’t ask “What do you like about A?” or “What do you not like about A?” Instead, ask “What do you think about A?” This really matters because these questions affect the data, which affects the product direction.
This all sounds like relatively simple advice but I’ve noticed over the years just how bad most interviews are, whether that’s in design or journalim. And it’s most certainly a thing that I struggle with because I just want to fix the problem desperately and give them help. But you cannot help the user during an interview.
You just have to sit there and wince.