Hi Peter, generally speaking, what is a route to consider for Canadians who are currently Software Developers and want to switch fields (ex. Product Manager) and work in the US for at a startup? TN NAFTA visa looks good although the "NAFTA Profession list" criteria is narrow (ex. doesn't include Product Manager)
Definitely, the TN is almost certainly the best option and the Engineer occupation can be used for Product-related positions that require a strong technical background.