The Aragon developers donāt collect any ETH or fiat from users, so that part is not true. And while there is a web client hosted in a central location at app.aragon.org, it is not the only instance: users could build and run it themselves locally, or even load the client directly from IPFS (again, a decentralized file system) on-demand without any reliance on any central points of failure. So it is quite a bit more decentralized in its operation then I think you give it credit for. And I think this is a meaningful enough distinction from traditional web apps or desktop apps that it deserves its own category.
That said, from a branding perspective, I do think ādappsā is probably not going to last long outside of a niche group of technologists, if at all. At the end of the day, these are just apps with a novel backend or distribution mechanism, technical details that most users donāt want or need to know about except in cases where something might be going wrong.