Yes, @morph027 is right. You can run as many virtual screens as possible with x2go, vnc, xrdp and others. You cannot have a "real" (as in real life) display, because you do not have "real" hardware in a container. If you need this, please use a VM and o PCIe passthrough.
How did you get X2go working? I can't manage it in a container. It looks like X2go executes /usr/bin/x2gomountdirs on log in, and that fails in a container.
My mistake. You can use X2go in LXC containers. There must be a bug in my X2go client. If I try the same configuration using an older version it works.