When you get these sorts of games in a franchise that's in a state like Metroid's, however, people get the impression that the series is dead and they're just fucking its corpse, milking its remaining fans who are just desperate for something out of the series for whatever money they can. Usually these games are mobile/browser games rather than proper portable/console titles, though.
The idea of having an online co-op shooter on 3DS came first, then they slaped on the Metroid name because it's a popular IP. They don't sit in a conference room going: "okay, Metroid. What do we do this this franchise?" Likewise, Star Fox Zero exists because Miyamoto's goal was to produce titles that would show the potential of the Wii U gamepad, not to "milk fans"
Games like Other M and Federation Force don't have the Metroid fanbase as target audience, Other M exists because they wanted a first party game on Wii that would appeal to the hardcore PS3/360 demographic. Whether we would've gotten a sequel to that game didn't hinge on what Metroid fans thought about it, but rather if it succeeded in bringing in new audiences. I don't know what their aim is with FF, I just think of it as part of Nintendo's current gen experiments with online games.
Nintendo won't develop a game specifically for Metroid fans, in the same way the new God of War reboot isn't aimed at hardcore GoW fans, but rather it's an IP they slap onto a successful template. In other words a TLoU clone in structure and tone, because it's what the market wants now. In the same way Castlevania Lords of Shadow was a God of War clone, to reach new audiences. And the same reason why Castlevania changed from classicvania to metroidvania; to artificially increase its game length. Difficulty had to be scaled down for the masses during the 90s, and that means a classicvania would last 2 hours on average. Nobody would buy a 2 hour game at full price, so they fucked classicvania fans because of that.
This is not the first Nintendo franchise to suffer from niche sales and outdated design (in the context of market demand), and won't be the last either. Fire Emblem fans can be happy thanks to the waifu elements that attracted new audiences, it's why the franchise is alive and kicking right now while Advance Wars fans am cry. This is the future: finding ways to expand the audience and modernise design, while doing their best to keep core elements of a franchise. Fire Emblem Fates isn't successful because it's a quality strategy game with deep gameplay systems (lol). Embrace the chibis and the waifus.
Metroid Prime Hunters kept normal proportions, and it looked great and played great on hardware far less powerful. So I'm not sure I see the necessity of FF's terrible style.
For you yes, but we're talking about the mass market here. Those who find navigating 3D space confusing and all that.