I think Evenepoel quite often expects more from himself given his training data, past performances and expected condition during certain races. And whenever he falls short he tries and find an explanation. Reality is, you are rarely at 100% during race conditions. Some minor illness, lack of sleep, build up fatigue, crash, ... .
I saw the crash btw. And it's hard to judge. He fell on his back and head for the most methinks. And whilst that can be bad, you can also get lucky. rolling motion, hardest part of the skeleton, helmet, ... .
Not sure how much the crash is truly affecting his performance. I think we just seeing an Evenepoel who expected to be close to his peak, and found out his climbing form in race fell short from training performance.
It's why he is looking for answer past the crash. Pollen, winter, ... .
I still think he'll come good with 3 more weeks of training , and a week of racing in his legs before the mountains hit in the TdF. But maybe he'll fall short. It happens.