Tanabe said he wants to continue with numbered sequels but I think it's silly. The Dark Samus/Phazon storyline is done, it's been like a decade since Corruption, it's a new developer and many long-running properties are moving away from numbered sequels. God of War dropped numbers, Halo dropped them, Assassin's Creeed dropped them, Monster Hunter dropped them. There's only a few holdouts like Final Fantasy, Dragon Quest and Resident Evil or clumsy transitions like Battlefield V.
The series has never been a big seller and and it's the perfect opportunity for a soft reboot instead of being held back by what came before it.