Right now, we don’t allow automated deposit of content without DOIs. However, we hope to improve support here in future.
For content you might like in your repository that isn’t an academic paper (like thesis, posters), we plan to add the ability to point users to separate systems for those. We’re focused on streamlining the deposit process for papers.
For papers without DOIs, we’re building out better systems to manage those. However, this represents a smaller and smaller fraction of articles. For the time being, we provide a route to deposit those manually.
It comes from "The state of OA: a large-scale analysis of the prevalence and impact of Open Access articles" and specifically figure 5.
The licenses suggested for papers are the most liberal licence allowed taking into account the relevant publisher, journal, university, and funder policies.