You can set the depth argument on git clone to have a shallow clone. However, that argument is not assigned on the git submodule update call. Either should the depth should be applied to submodule updates or a different arguments should be provided.
Use case / for what or how I would use it
To get faster builds and use less network. Especially for submodules, it’s pretty rare that you need the entire history.
For me it is a bug since I need different commit in the submodule depending on the version of the app I’m building. I can’t make my builds green because depth is always 1 for the submodule.
I believe we sorted this out via email the other day! Please do let me know if you still need assistance but it seems the ticket you submitted is now solved.