Having a hard time piecing together the complete picture of why that's the case (the team building priority), but here's how I understand it:
Debuff is the lowest priority given how many skills need to be used to set those up, and not to mention there's a lot of content out there that's so debuff unfriendly it's practically a waste of time to rely on those.
Mitigation to survive those overdrives if we can't knock them out of rage phase/ kill them fast enough.
Burst does more damage than nukes(?), but we probably can piece them together and say both are vital in stomping through enemies before they land a skill on you.
Which basically means if a debuff-centric hime doesn't do damage... don't include her in an end game team unless her mechanic literally breaks the content you're challenging harder than another hime you would've included?
Also, where do heals and orb reduction belong in this list?