The links where added to the socket one after the other. However, the virtual socket had a link limit of 1, so whenever a new link was added, the previously added one was removed. There is not really a reason for why the link limit should be 1 instead of something higher. I'm setting it to the max value: `0xFFF`. I'm also setting the `input_link_limit` to that value. Blender does not need this currently, but addons might have input sockets that allow more than one incident link.