Regardless, it’s an important life skill to learn that it’s generally not enough to ask people to do what you want, you need them to actually “buy in” to what you want, and then they’ll actually care enough to at least try make it happen.
This applies to managers and their employees, or also when trying to get on the ground employees to adopt a product initially sold to their manager/execs.
I don't feel the need to get "buy in" for bad faith managers.
An overly broad statement which, my experience, is not true. Managers come in many shapes.
Although, I suppose ironically, if you act in bad faith as a response to this perception, then I think that perception will quickly become true.
If the project fails, and the manager tries to blame it on you, they are de facto acting out of bad faith given the request. Documenting it just identifies this. If the project succeeds or fails, but no one blames you, then the documented request is just there for the record.