For many of us, that's a positive.

Could be, for not for $37.

There are other, equally basic for $0 or $10.

None equally integrated into the macOS system for that price though. Omnioutliner (the typical go-to native Mac outliner) is more than double.

Bike is usable forever (opening, editing, saving) without paying anything.

You only need to pay if you want to change some of the settings or use applescripts.