I agree.It's hard when some CH's send mixed messages,and are not consistent with what they say they want and like, and how they rate.I noticed the same discrepancy.I gave them a variety of names trying to hit the right niche..but all were rejected and I can't take anymore hits to my percentages,so it's not worth it to keep trying.
I agree with your assessment that the harsh ratings deter the best creatives from submitting names, so really it is counterproductive in my view, to getting the best efforts and names if you discount everyone's efforts..as creatives will give up rather than keep getting their percentages hit.I know I do.
In some contests even though I feel I am following the brief closely, and giving good names, every submission gets a nah. It doesn't inspire one to keep submitting.
I love the CH's who are liberal in their scoring,and will message you if they like your name and let you know you are on the right track,or ask you to tweak it if it's not quite right.It at least tells you where you are right,or missing the mark and where to go with it.Otherwise it's all a shot in the dark.