In one of your Swiss rivals, Tresorit, I don't have to create one single "Proton Folder to Sync" but I can define any number of folders on my computer to sync.

I really like that system because I have no desire to let my file-sync provider determine the folder-structure on my computer (no matter if that is Google, Dropbox, Microsoft or Proton). I have my files spread over multiple hard-drives and partitions and want to sync one folder here, another one there, and group it all by topic, not by sync-status.