You’re completely ignoring basically everything we see and expierience with suramar leading up to that; the struggles with mana addiction, the casual use of magic in day to day life, overcoming a deranged leader who is in league with the legion… All of these are echoes of the Blood elves.
And beyond that, where are the cornerstones of the night elf values in Suramar, the reverence for nature and the worship of Elune?
Lastly, Tyrande’s attitude is 100% in character with how she is slow to forgive and given that she could reasonably interpret the actions of Suramar as cowardice It’s easy to see how this would be a deeply engrained grudge.