The advantage of tags over folders is that things can live in different places instead of being constrained in one. It provides multiple axes of access to your information: say you have several projects with different collaborators, you can enter your data through the project or the person angle - you are not limited to one.
You can find the setup I used with Bear in this post, making extensive use of tags:
However, Bear is definitely not designed for linear ordering of contents. It’s just not its goal, it’s a notes app, not an outliner. If you want to order things, you need to do it manually with a note linking to others in the order you like, what we often call a MOC (map of contents) in the PKM space.
Craft might be an app more to your liking since it’s more designed in a more linear way (even though tags are coming).