I think this is where our different opinions come from, while we agree on the other aspects.
In my personal experience, I have never felt that the hire/no-hire decision relied exclusively on my ability of solving the presented problem; I have passed interviews where I did not solve the LC-style problem optimally but I communicated clearly, picked up on hints, was aware of when I hit "walls" and provided working but less than ideal alternatives when I could not figure out the neat tricks.
Reading through the thread it seems that my experience is not universal, and the majority here have had less pleasant interviews, so I understand where you are coming from.