Well I know people hated it. I hated that people hated it. It was a much needed drawback. It obviously needed tweaks, but getting rid of it completely was the wrong decision, IMHO.
People hated it because it was essentially RNG enabled crowd control; The same hate applied to dice rolls out of the saddle via bow attacks because once upon a time everyone carried a bow when they knew 1 in 5 or 1 in 10 shots, even at the lowest damage value, would throw a rider from their saddle.
You're recollecting a shitty game concept with rose tinted glasses at best, or at worst being intentionally and maliciously disingenuous to try and sway readers into a blanket nerf on mounts.
The reality is that anything at any time (even crossing a node line) could and would cause your horse to lose control and run you into a river or lake to drown you, or over a cliff to die from fall damage, or into a crowd of your enemies which would kill you.
You know why I hated it? I lived it, and I remember clearly because at that point in the game's life cycle, I was one of a handful of mounted players who played in spite of horse brain, because almost universally it was agreed that mounted was broken/useless because of the same horse brain. I remember the day they removed it and reworked the attack animations to be more adaptive to camera angle rather than fixed which made it so much better.
"It obviously needed tweaks" yeah, everything does, and the problem that always occurred was SV, who was incapable of fixing it, hence why it was scrapped permanently.