They are 28c so probably didn't have to be custom made, although the stacker is wider than any door I've seen before.
I would definitely be asking the question as to why the track is so high and why it wasn't pointed out to you that it would be. It sounds like it will be a tripping hazard which they should have made you aware off. It could be similar to what happened with my bifold window in that the window company went and made something that wasn't what the builder intended, in which case they may be able to get the window company to remake it. I wonder if it's possible to have it recessed into the slab at this late stage? That could be another option.