Should members of a board for a non profit be voting members from another organization that plan to use a product board members represent?
Legally a corporate body may be a person. Philosophically, neither it nor its board is a moral or ethical agent.
The individuals who sit on the board are the relevant moral or ethical agents. A corporate body may have rules that define what constitutes a conflict of interest and ethically obligate those agents toward certain actions. Or the corporate body may not.
Operationally, a board depends upon people with an interest in the corporate body which the board oversees.
Where one person may see a conflict of interests, another may see alignment. And the appearance of a potential conflict of interest is not in fact an actual conflict.