Its been like that a while hasn't it? I've never ridden it but have walked it and it doesn't look much fun. I know people on here do ride it but to me i'd rather be somewhere else. To be honest it also spoils it a bit for walking really – am i climbing a mountain or just a large flight of stairs…
I guess its the other side of trail sanitisation – make it too hard to cycle down! Seriously though i get your point about it being bridleway but the naitonal park turning it into a staircase, i.e. essentially a foot only route. Could they (should they?) not provide an equally well constructed route for bikes alongside?
This and the route down to patterdale has been touched on before and if i recall right someone on here has spoken about it to park rangers and they said just ride round the steps.