Here is my perspective on this:

• I think it should be an installer and the users should generate the components they need
• Upgrading means that they can choose to regenerate the same component with option of replace y/n

Why:

• I am a user of TailwindUI and some other UI components
• The times I never needed to change a bit something from there is almost zero.
• With HTML, a small tweak is needed in a project: adding a class, adding an attribute for accessibility ...

Thus a generator is the best option here. I want to generate the components that I need. If I don't need any customization, they will remain under app/views somewhere. But if I need to change something I can easily do it.

But if this were a library, it is hard to change just a bit of a component from the HTML perspective, especially if that is partial. It is hard to inherit it and add an extra aria attribute.

Someone might say: then let's make the components flexible so that everything that is needed to be added can be added via locals/variables. But that will mean a very complex code.

As an example: authentication-zero. It is a great choice to make authentication a generator because almost every time, something specific needs to be changed with authentication. In case of devise I almost always generate the views and refactor them with a different HTML code.