That's totally true, we also heard that the attitude is dramatically different if you're in the top of the batch.
Unfortunately, long-term performance is proven to not correlate well with performance during the batch, and YC are transparent about it. So I wouldn't recommend over-stressing it.
It's true that the business is governed by power laws at every level and you can't ignore those and succeed. I hope that doesn't prevent people from still being decent to each other.
That’s the type of thing that you have to earn, and if you earn it you don’t need it.