Cross member to attach the front of the oem auto tranny skid plate. Have it on my '04 Rubi, and it's also on my previously owned '03 X.
I used to hear a clunk on my X when I went around a certain corner that had a dip the front left tire would go into. Took a while to diagnose, but found out it was the drive shaft hitting that skid plate. I never did anything about it, it did not happen often. Some have notched the skid plate to provide more clearance. I've never experienced my drive shaft on my Rubi hitting anything, even after the OME lift.
Since you don't have the skid plate, no reason you couldn't remove that cross member if you don't want it there, but I imagine it provides a modicum of protection for the auto tranny.