As was mentioned, it really depends on you, how you treat phones, and your comfort level. I know people who drop their phones multiple times in a year, for those people it would seem to be a no brainer. Then again, I know people who buy new phones every year, so they don't have the same concern about their phone breaking, insurance does nothing for them.
It comes down to, how big a risk do you think it is that you might drop or bend (such as being in a pocket) your phone? I know some have concerns after seeing the bend videos, as well as the reports of people's 6P becoming slightly bent (will not lie completely flat when placed front side down on a table).
I'd say if you are unsure, then go ahead and purchase Fi Protect; one of the nice things about it is that you can cancel at any time. I can see many people just wanting it for a year, while the phone is "new", and as it gets older they cancel Fi Protect, as they start thinking they can buy one of the newer (and nicer) phones if they have an issue.