In some situations, they are and the advice taken is assumed by the recipient to be such. Here's a hypothetical example. A response is, I have run my **** in Auto for the last year with no issues (what GM Legal considers the subtle difference between Auto and AWD is unknown to me). The recipient takes that to be expert advice (based upon experience and potentially "holding out") and drives the **** in Auto mode at all times. His transfer case then fails and he takes his **** to the dealer for warranty service. The dealer notes the transfer case is set to Auto and questions the owner who responds truthfully. GM refuses the repair under warranty citing a failure to follow the user manual. The owner sues GM *and* the individual providing the advice. Now, depending who is on the bench, this case could go in several directions including dismissing the claim against the individual providing the advice ... after, of course, that individual pays substantial legal costs (multi-state civil cases are expensive). Here's another example: If the vehicle is always driven in Auto mode, it is safe to assume that very same owner/driver would park on a hill where there is mud, wet leaves, snow, gravel, etc. After exiting the vehicle, it slides down the hill, striking another vehicle and injuring or killing someone. Read page 224 (2018 Yukon Owner's Manual). In layman's terms, you're screwed, along with anyone else involved in that decision by the owner/driver.
LEXISNEXIS searches are not free. You buying? (I bill $350.00 per hour on top of that).
There is a trend today that many will not take responsibility for their actions (or lack thereof) and not be prepared for the consequences of their actions. Owning and driving a vehicle carries with it various responsibilities (legal and otherwise). Knowing the proper operating procedures among them. When the answer to a question is clearly stated in the manufacturer's Owner's Manual, that text is the only valid and proper response. Conduct yourself accordingly.