I think the Roy/Aisha/Nex love triangle in Winx season six happened because Rainbow came up with a better idea for a new Aisha love story. Unfortunately, they’d already introduced Roy, so they had to figure out how to write around him. A love triangle was a terrible way to do it. It created a bad first impression of Nex and this new couple.
I hope Rainbow will repair the damage and show how Aisha’s relationship with Nex makes more sense for her story.