@Vitor Pamplona of course, there are apps that cant be built even with a Proton Drive like API. Most notably apps like Twitter or any app that needs aggregation of data authored by multiple people and custom API endpoints that are tailored to the UI needs (backend for frontends) ... but I always argued that these are lost cause. I just want to see something like Proton Drive but open for all quiet apps to flourish there... I dont want the next Obsidian to be closed source, nor its cloud sync to be centralised.