Earlier quoted context omitted.
Actually you are so right... And I do not understand why google doesn't seem to solve that problem... I mean I really like PWAs. But while they are around since a while now (about 2 years?), the pain points have not been addressed so far. - Privacy: There are multiple issues related to privacy here (transparent updates, Serviceworker running in the background without the user knowing about it), and when I see it how…
You can make a virtual file system in the browser using localStorage. You can then sync it across devices and browsers via a server. You can upload files to the PWA using drag-n-drop or file input. You can also send files from the PWA to the device file system. I think it's important that Web browsers can't automatically control the device hard drives, imagine if all web sites you visited would be able to do rm / -rf…
That way it can't do much damage and when you trust it, you can give it more access.
I use the localStorage as a cache for some of the offline capabilites but as a persistent storage it sucks as you can't easily open the stored "files" with other programms or PWAs.