Good points. I think it boils down to an issue of semantics, though. FastAPI effectively eliminates (or hides) the View layer by allowing the Model to determine which fields it should allow the View to access. If you don't believe this is explicit enough (which could be a fair argument!), it's perfectly reasonable to suggest this "breaks" standard MVC conventions (as it can easily be construed as the View being part of the Model!).

I would argue that it merely allows for more automated (albeit implicit) generation of a View.

The goal here was to simplify the API endpoint creation process for the vast majority of use cases, and provide a standard output that could be easily recognized and consistently managed by any external software.