Not the right IP for them. Not everything needs to be really hard or Souls like. I would prefer Retro make Prime 4. I would accept Platinum making a Metroid Game to right where Other M went wrong.(this time with no Miyamoto forced controls)
Metroid is a game about exploration and action at a fast paces gameplay. When it's a series about backtracking it just does not fit Samus to be watching stamina and crap like that. It slows the pace down and that is not Metroid. No keep the Souls junk away from Metroid. Not a good fit. Makes as much sense as a Starfx Warriors game.