The upload limit for files set in course settings normally does not apply to teachers of that course.

Reproduce:

1) Go to a course in which you at least have teacher role
2) Go to course settings and set the maximum upload size to a limit.
3) Add a new file resource, the upload file dialog still shows you that file size is unlimited, since you are a teacher
4) Go back to the course, turn on edit mode, and try to directly add a file via drag & drop on the course -> you will get an error: "The file is too large and cannot be uploaded"