Yes, I likely oversimplified her message, sorry. She never advocates praising effort in isolation from outcome. She advocates praising effort as the key factor in successful outcomes, and analyzing failures to understand what caused them and how you can grow your skillset to avoid them in the future. Her concern with a fixed mindset is that a loss/setback simply means someone else was better/smarter than you and there isn't much you can do about it. That or, to protect your ego, perhaps they cheated or the judges liked them better, or they were born to wealthy parents and had advantages you didn't or whatever other excuse people come up to explain a loss when they feel a loss labels them as a loser for all time. If you have the mindset that you can learn/improve from these experiences then a loss/failure isn't something to be hidden in shame, but something to be analyzed and used to make yourself better.

She has a story about a parent whose daughter was competing in gymnastics and at the local level always did pretty well without much practice. She went to a regional meet and did well relative to her skills but was outperformed by others and ended up not winning any medals/ribbons. On the way home the dad basically told her she didn't win because she didn't deserve to, i.e. the other competitors had put in more practice than she had and it showed in their performance. He didn't say 'they beat you because they are more talented' or 'they beat you because they are superior athletes', those are the kinds of statements that imply there is some core quality that the winners had that his daughter didn't have and thus she could never be better than them. Instead he basically said 'they buckled down and put in the long hours, if you did that you would have had a better chance'.

Dweck pointed out that he wasn't saying this to be a dick, and of course feedback like this much be couched correctly for people to hear it, but he wanted his daughter to know that to compete you have to put in the effort to learn/practice. If others put in more effort than you then they deserve to win, all else being equal. The story ended with her doubling down on her effort/practice (since she realized her local competitors which she could easily beat were only indicative of her talent vis-a-vis them, not some absolute barometer for her skills) and going on to compete successfully at a national level.

You are right that if I try and deliver some project at work and it fails I can't tell my boss 'but I tried really hard!' :) That said, if you look at most successful projects/people you see a LOT of hard work at some point to deliver on things. Some people make it look easy, but that is likely because they have done all the hard work years earlier building their skillsets. If they have done more of that than you then it shouldn't be surprising that their skills seem so superior to yours. They weren't born being masters of anything (hell, babies can't even manage to not shit themselves for a few years :)), but they put in time and effort even when there was little/no reward for that investment (in the immediate here and now, obviously there is reward later when you are able to do seemingly super-human things easily).