You're right there. I was pretty psyched when their calendar came out and originally I did like the many services, one source approach. I've since switched to a more compartmentalized setup, and it seems like those of us in this camp are just a vocal minority with too many opinions 😄. It is pretty awesome that more and more people I know are using proton's email service, let alone just understanding the value of privacy respecting communication apps.
EDIT: realized this was for desktop, so removed the original list of mostly android apps. Here's my go to desktop apps:
Lollypop - music player
Invoiceninja - open source invoicing service
Meld - file/folder comparison
Librewolf - hardened Firefox
Joplin - notes
QEMU/Virt-Manager - virtualization for that one windows app you still need
KeepassXC - password management
Element-desktop - Matrix client
Gparted - no fuss partition management
Lutris - game launcher that works with epic games (among many others)
PDFarranger - best PDF management I've found on Linux Soundconverter - easy to use file converter
Restic - backups
Fdupes - duplicate file finder
Freetube - privacy respecting YouTube client
Paperless-ngx - very well built electronic document storage. Must be run as a server.