The reality is that the "auto Hand brake" does nothing in just about every track in LFS. It is just there to keep you from moving by accident on the start. the only real place it does something is Blackwood because of the hill you start on.
So, for the most part, anybody who does not like it can pretty much ignore it. I do not see it as a big deal. On most track you can pretend it is not even on.
The reason it needs to be there is because unlike real life, we do not pull up to our starting position before each race. We teleport there, and if there were no Auto Hand Barke, we would all teleport on the starting grid of Blackwood, and anybody who did not put there foot on the brake, or hit the hand brake, would just roll down the hill.
But again, on most tracks, the Auto hand brake is 100% meaningless, and to argue over something that does nothing on all but one track seems like a waste of time.
People who want manualy release a handbrake, for added realism, have probably never been in a real race car. I have been to a handfull of tracks and have never sat at the startline with my handbrake on, EVER.
So you would want to add something that would probably never happen (letting go oh the handbrake) on any of these tracks in real life, to add realism. Makes little to no sense.