is not a bug, it is a different setup… in detail view, you would have to add a button for the new form… in list view, since is just a list… Glide can integrate all functions for that list.
A Details style layout could potentially have multiple inline lists, so the built in Add button at the top right of the screen becomes a little ambiguous when you have multiple sources of content on the same screen. Plus, when you are in a details style layout, you are usually attached to a single row in the tab’s source table, so the top right corner is reserved for the edit button for that particular row (if you enable editing).
My personal preference is to always use a details style layout almost exclusively, and then add a floating Form Button for adding new rows. I just like the look better. I rarely use the build in Add or Edit buttons at the top right of the screen, and instead use buttons or floating buttons with Form or Edit actions.
Although I think both of the current comments give excellent solutions for getting around the problem, and I really appreciate and will use these solutions, for now, for consistency, I still think the behavior of the create a new instance of a list item element should change as little as possible from one context to another. This is the way you make a system easy to use for a beginner.