probably a pretty basic question. However, is there a way to restrict users from uploading files (flatfiles) in a project by user group, while still retaining the ability to change the flow, create new datasets and recipes? I was thinking that this could be handled via modification of user properties.
There is no option to disable upload for groups while still allowing to create datasets on this connection. It's either both permissions available or none of them.
I would suggest creating separate connections for each group and grant appropriate access to each one. However, in this case, you might need to disable built-in file systems connections (filesystem_managed, filesystem_folders and filesystem_root) so each group can only access their group's custom File System connection. You will also need to disable the "Default" file system connection. For this navigate to Administration -> Settings -> Engines & Connections and disable "Uploads in default location" option.