No. We won't increase the column limit soon. First we would need to rework all internal cell datastructures like I did for sheets in 3.5. We still use fixed size containers for columns. That means that increasing the column limit will increase the the memory needed for every sheet extremelly. The column limit of 1024 is a design decision by us.
If you are really in need for LibO with a bigger column limit you can easily build one yourself and I tell you the line you need to change to increase the limit.