I feel like Nintendo is incapable of making a good Metroid game at this point. I actually believe that. They lack the ability to be bold with their game designs, bold in the way that would suit a new Metroid game. I think they just ain't got it.
They need to find capable people who know about Metroid and care about Metroid and let them MOTHER FUCKING MAKE A GAME! GRRR!
I very much doubt that. Nintendo
could make another fantastic Metroid game if they wanted to... emphasis on the word
could. The problem more seems to me to be that they just aren't personally interested in making a solid, traditional sidescroller Metroid game for whatever reason nor a game in the vein of Prime or Prime 2.
Instead, noting the trend from Fusion to Metroid Prime: Hunters to Corruption to Other M to Federation Force and from what Nintendo have discussed regarding the future of the series from here it seems really clear that they just care less and less about a game where a lone Samus Aran finds herself in a desperate situation on a hostile planet and manage to fight against the odds to recollect her abilities and escape the planet all by herself, and instead seem fascinated by the idea of making her interact more and more with the Fedeartion, other bounty hunters, and other such NPC characters and an increased focus on direct-storytelling as opposed to discoverable lore, shifting the games from being focused primarily on Samus's/the player's actions at helping her survive to a flat-out narrative and NPC interactions being the primary driving force.
This of course both limits the feel of how isolated the worlds in the game feels and more significantly limits the feeling of how much control the player really has over where they're taking Samus and when as Samus is just being more and more lead around by a plot, limiting the need for exploration and player agency concerning what to do from point to point in the game. These are all naturally rather strong negatives for fans of classic Metroid games, but for whatever reason, especially based on FF and what they've discussed about their future plans for the series at E3, it seems the direction their determined to take the series for the time being, regardless of how far that takes them away from the core Metroid gameplay and the elements that make Metroid games, well, "Metroid."
Now, of course, Nintendo could stop doing at any time. I still fully believe they're capable of making an excellent Metroid game, if that's what they actually wanted to do. There's no doubt in my mind that the studios they have working for them, such as NLG and Retro Studios, are still fully capable of doing that. They're clearly still extremely talented developers and more than capable of developing such a game if that were actually the game Nintendo asked them to make. The problem in my mind is, for whatever reason, they either just don't want to (which seems to be the case, IMO) or otherwise for some strange reason think the path to success for the series (despite the success of stuff like Ori and the Blind Forest and the Bloodstained Kickstarter showing there's demand for 2D Meroidvania games, but Nintendo unfortunately doesn't exactly have a history of being swift in taking note of such things and actually adapting their plans in response regardless) is to try and force more narrative and lore and NPCs and shitty federation friends and stuff in there, despite that... not exactly working so well thus far and doubling down on it anyway. All we can really hope I guess is that whatever it is that's causing Nintendo to think this is a great idea for the series is just for them to get it out of their systems and move on and back to the classic Metroid style, hopefully sooner then later.