There are all ways to manage horses and each one of us comes to our own ideas from our experiences.
I would avoid at all cost wooden barns and barns with lofts, but would prefer concrete stalls properly bedded, maybe matted also.
That is because in my experience, hay stored above caused more dust and, being in two barn fires, one caused by hay in the loft somehow getting a hot spot that ignited it and the reality that wood barns burn down considerably more and faster than others, I just rather avoid one more risk when we can do so.
On the other hand, having grown up with concrete floor stalls, I know horses, even those living there 24/7 all their lives, were perfectly fine in there and better than in any other kind of stall flooring.
I would say, each one of us can avoid what we don’t care for and if lucky, get in our horse care what we prefer and more important, make whatever we decide work ok for our horses and ourselves.
OP, if you have a loft, you can still not use it if you don’t like to, or go ahead with the information you have now and do the best with it you can.