I've said it before, but no matter what scoring method is used, you'll always have a core of people who believe it's rigged against them. This choice is transparent, not mathematically complicated, and prevents downward manipulation. Such a fundamental change is never going to be ideal when work that has existed for years under different criteria is involved, but the solution offered for dealing with existing work is reasonable IMO.
As to contests, I don't believe the shortlisting was ever based entirely upon score. The one time I placed was ( as best I can determine from conversation at the time ) because very few people were on theme in a sponsored contest. My score and vote total were nothing to write home about from what I remember at the time, and I believe that was the reason for the complaints that started the conversation I'm talking about. If it was only score that determined the shortlist, I wouldn't have made it.
I've seen other stories place where the score wasn't in that upper echelon, but the story was most certainly deserving. I've never seen a winning story that didn't deserve to be there. My anecdotal observations indicate to me that solid stories had an opportunity to be considered regardless of the raw number of the score. Some probably slipped through the cracks due to large numbers of entries, but there was always opportunity for a well written story.
The new scoring method in fact removes the reason I stopped participating in contests. The more nuanced voting in contests hurt the long-term exposure of stories that didn't place, and there were too many top tier authors ( top tier in quality/talent, not followers ) participating regularly to leave any openings for anyone else. Thus participation was a net negative for me. The same story published outside the contest would score better, and thus gain exposure over the long term that outweighed the short term bump from contest highlighting. Absent the liked-it-but-didn't-love-it 4s that contest voting typically produced, there's no downward pressure on long term exposure from the new scoring method.
( Absent the by-category toplists, long term exposure potential has been seriously curtailed, but that's a different discussion )
The short version is that I think people are reading too much into the documented shortlisting process and unnecessarily worried that author followings will push everyone else out.