This rod was here when we bought the house. I sewed 4 lined grommet panels together and they have been fine without a middle support.

If you have a telescoping rod, you will need a support on the middle. If you have one cut to size, you won't for this size. It is fine for the bracket to be in the middle for a split stack.

You shouldn't need one for a wooden rod at that length, but I have one in my living room (over sliders) and have noticed that after 10 years it is starting to sag a bit in the center. I just roll it around and it seems to be ok. There is special hardware that allows the panel to traverse over a center support but it's for pinch pleated drapes. If you have center draw panels, there is no issue with having a center support.

I put a piece of wooden dowel inside of mine to stiffen it up.