Thank you for the opportunity to help you with your question!
Biased questions are many that asks for flavors and forcing to adopt some. There are some related behaviors and attitudes as well that forces the question turned into a biased one.
It may depend. If they are asking something like:
Is It Preferred To Have Flavor A or Flavor B
That will be subjective and primarily opinion-based as every one has their favorite choice. But if the question is something like this:
Will This Affect The Flavor of The Coffee
That will not be subjective due to the fact it is just asking of the flavor will change or not. This is the situation with the question you posted. The asker just wants to see how the flavor will change, not which one is the best and why. I hope this answers your question!
Please let me know if you need any clarification. I'm always happy to answer your questions.