A duet is a type of collaboration. A collaboration is any kind of working situation where separate entities contribute to a project. It can be equal or someone else can give more. It's not an either/or thing. "#1," "UNUSUAL," "BLACK DIAMOND," "FAKE," "Grotesque," etc. These are all equally shared, some of them are hers, some are the other artists. They're all duets and they are all collaborations. There's no difference.
At their cores, Namie and MAX are still the same kind of artists they were when they debuted. I don't know what drastic changes you're talking about. At the moment, they're even both recording European produced dance music. Like... Anyway, unlike many of Namie's past collaborators, MAX, are in fact her friends, people she has spent time with outside of the entertainment business even after they split. They have done more than just work together. For the last time, if they decide to work together through this voting thing it will be done through themselves. No one will be forced to work with anyone for the fans. I don't know what your thought process is, but you make it sounds like because the idea didn't come up organically or that it was a suggestion that it shouldn't be done. In reality, a ton of Namie's collaborations are ones that she was invited to do. She was not interested until she was asked. This would be no different and no less special.
You said they would have equal parts "A collaboration would indicate they'd have equal parts btw." So, I said a collab =/= equal parts, like duets & such do. Yes, a Duet is a "collab" but it's a specific type. I think it's clear I know what the words mean when I said an Utada Collab could be her just writing or producing...There is a difference, as a Collab isn't always a Duet, or Quartet in this case. This is being asked for, FOR Namie, not "What's the next Avex Project". So she's automatically lead, anyone chosen is a feature.
You're misunderstanding everything...O.o
Though I will say they're different now. MAX is way more Pop, Euro, Techno, EDM, etc. They haven't changed drastically, just variations & extensions. Namie has changed quite a bit from them & her older stuff. I NEVER said it couldn't work, I said considering the factors it's better if they do it on their own. Reunions are best when genuine. O.o That's when they really have fun.♡ This doesn't mean it will fall.
Also, mainly the recent collabs (Guetta, Zedd, etc) have been invites. She met TLC in the past & worked w/ them for her album once, then for HoM pv & Waterfalls. She's clearly friends w/ AI, Verbal, etc to say "not interested". Those were genuine and all. +They DIDN'T HAVE VF ISSUES. None of these were fan picked nor were they Reunions.