If you are not allowed to stay mounted during allcharge as cavalry there is no point of even allowing cavalry, dismounted cav is just bad in allcharge...
mounted cav in all charge is the most pain in the ass i can think of. I think no one except the cav enjoys them being mounted during all charge. A good cav is really effective in a classic linebattle, but in all charge, where everyone is basically playing alone and everything is basically open melee, it gets more op.
From my experience ~60% of the Cavalry dont even get into melee cuz they get shot in Charge, out of Line/Formation or just shooting when cav approaches. Heavy cav can be lucky and tank a shot but Hussars go down immediately + you should consider OA doesnt count for cav either or at least when he only gets dismounted. Last seasons of NWBC were mainly camping till allcharge which would make cav absolutely useless cuz if you try to charge enemy team camping you dont even get 5 kills...
+ consider its not a classical LB, its nwbc where all regiments coordinate and communicate which makes it impossible for the cav to catch a random line somewhere ^^
edit: most dont even seem to know how to play vs cavalry, that shouldnt be a disadvantage for cavalry just because most inf doesnt know how to deal with cav.