No, the cavalry moment is shit, to be sure, but the story isn't random. It's just inept. The main exception to it is the obvious rewrite around Ysera, who was obviously meant to fully return in the role, built up for the last expansion in this direction, only to be sidelined for her even more boring daughter after (night elf) complaints, making her role in the Dream pointless and still ending up with Malfurion written out at the end, just in a slightly different way. But every part of the oathstone -> failure -> fulfilling of individual flight arc -> empowerment by the planet arc was consistent throughout. It is rushed and of poor quality, but it's coherent in the beats it means to hit.