Yes, Wikipedia's Neutral Point of View is sound policy, because it helps people trust the website. Without the neutral point of view, Wikipedia would be a debate website, not an information website. It is important that Wikipedia remain neutral in order to be seen as credible by people who use the website.
Yes, Wikipedia's Neutral Point of View is sound, because it operates like encyclopedias that are printed operate. If Wikipedia were to allow people to take a side, their website would quickly degenerate into people posting their opinions, which would be vicious and inflammatory. Remaining neutral is the best way for people to use Wikipedia.