My understanding is that the intent is to update other applications with this design over time.
All of the label and value munging / collapsing / rendering code is in this gem. It is not exposed in a fashion such that it is feasible to create this view in purl.
The code which is inherently purl specific is in a value renderer which is in the purl codebase. (The purpose of adding the value renderer abstraction for related items was to make that possible.)
refs https://github.com/sul-dlss/purl/issues/799
Required by new design.