More than a dozen years in tech have taught me that roles are simply ways of expressing organizational wishes. You want someone who thinks about something as a product? You open a PM position. You want a team lead? Here's an EM position. Job titles are elements of fiction that allow us to play that RPG called work under different angles. What you ultimately bring to work is your unique mix of talents and experience.

Some people will often break the boundaries of those roles, though, and that's ok. They have ideas and might even come up with their own job titles. An organization must be smart enough to let that people grow and thrive. That doesn't mean one cannot thrive as a PM, or do great work; it's just that an organization usually cannot invest time in deeply knowing who they're getting onboard and so offer precooked roles.