I just realized three problems with making a Metroid game for the Switch:
Length, breadth, and depth.
Super Mario Odyssey, The Legend of Zelda: Breath of the Wild, and Super Smash Bros Ultimate are games that excel in all three categories, because of replay value / game length (length), the openness of design (breadth), and the complexity of said design (depth). Metroid games haven't really been known for any of these things.
Problem one, the length of Metroid games... They're usually short runs, and they reward speedrunning. The replay value has been in getting better times and finding exploits to shave off frames here and there. The longer a standard run of a Metroid game is, the lower the usual replay likelihood it has.
Problem two, the breadth... Most Metroid games fake an "open" design with multiple branching passageways and "sequence breaking" secrets, but all in all the Metroid games follow a linear progression, it seems. And no game in the series pulls off that bait-n-switch (haha, puns) better than Super Metroid.
Problem three, the depth... Most Metroid games don't allow players to really experiment with systems or advanced moves outside of two or so rooms (optional ones for the sake of getting the last few expansions in a game), and so interesting moments like trick shots in BotW or scaling the side of a building in Odyssey don't really happen in a Metroid game. Or, if they do, they happen very, very infrequently.
Nintendo Switch cartridges have a METRIC TON of space on them, so it would seem criminal to not utilize it to the fullest, right? Well, then, for a Metroid game to be a smash hit on the Switch, how on earth could these three problems be resolved? The games have to be longer (or more replayable), they need to be more open (and thus more flexible in progression and story/narrative), they need to be more systemic (like the immersive sims-like additions in BotW), they need to be more complex or customizable or configurable, they need to provide sufficient backdrops for variable, interesting gameplay...