actually, the observed behavior makes macOS app centric. for a truly document centric system, opening a document should do exactly that and nothing more. what instead happens is that the preview app is started, and it remembers its previous state opening all the other documents it had open before. from an app-centric perspective that makes total sense. and i also approve of the concept of an app keeping its state.
to make the preview app and other apps document centric, the app itself needs to become less visible. for example the function to close the app could be replaced with one to close all documents. this would offer a document centric intent behind the close action. and for those cases where i don't actually want to close those documents, but just need to move them out of the way, different mechanisms are needed. functions like hide or suspend for starters that allow the OS to actually remove the apps and documents from memory but without changing their state to being closed. work spaces are also a possible concept.
another approach that preview could easily implement is to hide the documents that i didn't ask to be open at this moment. so the documents are still there, and their state is preserved, i just don't see it until i switch to that document. this would be similar to how at least firefox handles tabs. the tabs are there, but they are not loaded until i open each one of them. in the same way preview could remember all the recent documents, until i explicitly close a document just like i would close a tab.
a truly document centric system needs at least proper interface design and language, but parts may also need a redesign of core concepts. for example, when opening a document, i should be able to specify what kind of activity i want to do with it. depending on the chosen activity the right app that offers that activity will be started. currently i get to choose which app i open a document in, and there is one default app, and if i want another, i either open the app first, and then tell it to open the document, or i specifically choose the app that this document should be opened with. again this looks very app centric.
in a document centric system i expect that i open a document, and then all the possible actions on that document are available to me. but different actions can be provided by different applications which requires that apps interface with each other in a completely different way.
to make the preview app and other apps document centric, the app itself needs to become less visible. for example the function to close the app could be replaced with one to close all documents. this would offer a document centric intent behind the close action. and for those cases where i don't actually want to close those documents, but just need to move them out of the way, different mechanisms are needed. functions like hide or suspend for starters that allow the OS to actually remove the apps and documents from memory but without changing their state to being closed. work spaces are also a possible concept.
another approach that preview could easily implement is to hide the documents that i didn't ask to be open at this moment. so the documents are still there, and their state is preserved, i just don't see it until i switch to that document. this would be similar to how at least firefox handles tabs. the tabs are there, but they are not loaded until i open each one of them. in the same way preview could remember all the recent documents, until i explicitly close a document just like i would close a tab.
a truly document centric system needs at least proper interface design and language, but parts may also need a redesign of core concepts. for example, when opening a document, i should be able to specify what kind of activity i want to do with it. depending on the chosen activity the right app that offers that activity will be started. currently i get to choose which app i open a document in, and there is one default app, and if i want another, i either open the app first, and then tell it to open the document, or i specifically choose the app that this document should be opened with. again this looks very app centric.
in a document centric system i expect that i open a document, and then all the possible actions on that document are available to me. but different actions can be provided by different applications which requires that apps interface with each other in a completely different way.