That all depends on what you want to do with your drone.
If it involves making money or getting anything of value out of it at all, then yes. This includes:
- Creating real estate photos for a friend regardless of pay you get (the photos will be used for commerce).
- Selling aerial photos you've created in any online or physical marketplace.
- Getting hired to survey agriculture or infrastructure.
- Using your drone to create b-roll for YouTube videos that you've monetized.
That last one sounds silly but the FAA has actually fined YouTube creators with monetized channels who have used drone footage without a Part 107 license - because they're using this drone footage to make money through advertising. They're not my rules, I'm just the messenger!
Even if you're not getting anything of value out of flying your drone, a Part 107 license is still a good idea. It will teach you the rules about flying. You will become more responsible. You will have clout, credibility when approached by someone, like law enforcement, wondering what you're doing.
And then if you do want to make money with it, you're already licensed!