You can install Proton Docs as a PWA on desktop but you can't have separate icons for docs and sheets currently on the taskbar or dock. Having separate icons instead of the current way where it opens up a generic window would be useful to because you can make it feel like you have desktop apps without actually having or needing desktop apps. It could make things simpler for non techie users who are used to separate icons but don't know what a web app is.