Data pages are always in an advantage position comparatively to top level page. Data page ease access to data in an application. It provides data on-demand access as per your business requirement, though top-level pages are static and don't have any mechanism like "Load Management" to refresh the content of data page at the certain interval.
Editable Data pages let you loosely couple the business logic, source and other useful configuration from data reference. It let the user provide filtered data as per key passed.
Top-Level Page is a structure in the clipboard for data manipulation and other usages in the application while Data Page is cache kind of data which is made available to the application on request and it can be sourced from external sources as well.
The Top level pages doesn't have the refresh strategies which the Data Pages can provide, due to this the top level pages might return the stale data whereas in data pages with the refresh mechanism you can always work on the live data.
I think I am a bit confused. Let's say if I have a flow action and on the section for that flow action I would need to show some sort of data of some object and be able to amend it and submit it. Would I be able to use Editable data page for this at all?