I think a lot of what you said is true although she wasn't that great at her GP events last year when victory was pretty much guaranteed.Maybe it's time to work with a sport psychologist.
She maybe have the unbeatable who got beaten syndrome.
That confidence issue is there maybe since her last junior season.
I mean in her 1st junior season she was unbeatable. Even though she botched the quad all the season, she was consistent on triples and was always winning with big margin. But that Kosto's win at JGPF with big margin due to pcs may have shaken things. She started to do more mistakes.
When she's against opponents who have realistic chances to win if she falls, she gets nervous.
If Kostornaya didn't have that 8 points lead maybe Trusova would have been more relaxed like at 4th stage CoR.
It might be when all is said and done a case of simply growing up and starting to think more and becoming less fearless. And of course the more she skates unclean the more her confidence gets shaken and she can't let it go. Letting go of a bad skate probably gets harder to do the older you get. This in top of the media calling her the "Quad Queen trailblazer" can't help at all
