A high level but interesting write up of how Figma (a browser-based collaborative design tool) behaves like a file editor (their term), and how it overcomes the natural affinity of web apps to RDBMS-backed CRUD persistence patterns.
Upspin is an interesting project made, partly, in response to how modern web apps handle your data.
It's a way to get a named file interface to stuff that doesn't expose files and directories (folders).