RNG is RNG. Theres no one questioning that. As someone who is a fairly avid mount collector, I know that all too well. It doesnt make anyone feel any better when they run thru all 16 bosses and nothing drops for them.
Some fixes could be upping the drop rate which I believe is 5% to maybe 10% seeing as it is possible and it seemingly likely that no gear drops for anyone on a boss. Another way is to make the bags that you get from no winning to include some sort of worthwhile item, be it a pattern or maybe a stack of mats. Getting 28.5g is such a pitiful amount of gold that it is not really anything.