Desexing doesn’t change a bun’s personality, but the hormonally driven behaviors will go away or be reduced. It’s stressful for her to follow you around in vain attempts at courtship. It certainly was very stressful for my Bam, I tried to block him from going near the the dog with a baby gate, he threw himself at the gate and gnawed at it endlessly, so intense was his need to be close to her. It wasn’t good for him.
After he was neutered he returned to his “old self”, so I think having him neutered brought out his personality more rather than less. He’s a very cuddly bun, and he’s become increasingly cuddly over the years.
Right after a spay, the bun’s hormonal behaviours can become enhanced, this is a phase known as a “post-spay craze”. It happens to both boys and girls but usually lasts longer in girls. During this time the bunny can display, among other things, territoriality and cage-aggression. It’s normal and goes away with time.