If they had, everybody who complained about Other M or Federation Force would complain about it, and trash Next Level Games anyway.
I mean, when you see the absurd hate that can spew in Metroid threads about the tiniest details, think about how a game with a Samus like
this:
... would be received.
You have one group of people who'll go into holy war for any Metroid game that doesn't copy the Super Metroid canon, including for the silliest thing.
Next Level Games likes to play and turn around franchises given to them, look at what they did to the Mario crew in Mario Strikers. It would have been shot to Hell by so-called "fans" no matter what, the same "fans" that hate NES Metroid because it's too old, hate Metroid II because it's too linear or in black and white or without an automap, hate Fusion because of the Adam computer and linearity, hate Echoes because of the dual worlds and the corrosive air in the Dark World or the ammo for the beam, hate Corruption because Samus isn't stranded on a planet and communicates with people, hate Metroid Hunters and Metroid Pinball because they're spin-offs, and obviously hate Other M.
You know, the "fans" that like one or two games in the whole series and despise everything else.
You know? People would have been happy with that art style if the game was a 'standard' Metroid game (which it was going to be, as the original Next Level Game's Metroid concept was a 2.5D Metroid they was going to pitch to Nintendo but got push aside once Nintendo told them "Go make Luigi's Mansion 2!" and they were like "Welp, lets give that a shot guys

!").
The problem isn't that the 'fans' are pissed about anything not like Super Metroid/Metroid Prime.....they are mad due to not getting the game they wanted for over 8 years

. And its not like Nintendo said "We are done with the mainline series after Prime 3" or anything like that, they moved on to Other M a few years latter and that might as well been the Sonic 06 to the Metroid series; a game that is very, very polarizing for a number of reasons.
Granted, Other M's quality is no were near close to 06 (Other M is a very polished game despite its many issues), but its impact was the same; shattered the series and making fans....livid, to put it lightly. But unlike Sonic 06 where we got Unleashed, Colors and Generations making up for how bad 06 was, Metroid fans got nothing to make up for Other M, thus coming back to Federation Force. It might be a good game (heck, with Next Level behind it, I expect it to be a great game

!) but after so many years (5 if you count Other M, 8 if you don't count it) without a Metroid game, people didn't get what they wanted.
That is why that silly petition was made; to show Nintendo that they don't WANT Metroid spin-off, they want a full-on Metroid game. Was the anger justified? No, I don't think so; Next Level is a great developer for starters, so that will lead to Federation Force being a good/great game. Secondly, the 'Prime' label being used again after 8 years means a new console game is coming (similar to the Prime Pinball and Prime Hunters Spin-offs), likely on NX next year. Lastly, while not 'Metroid', people who love the series have a lot of games to play that fill that empty 'hole'.
Between Kickstarter games that look to really play with the Metroid formula, games that heavily mirror the NES game like Axiom Verge, or games like Guacamelee or Shantae: Pirates Curse that while not copying the formula 1-to-1, have elements from the series present in creative ways; the spirit of Metroid is very alive and well.
Nintendo being behind the curve with the series is just this "Oh well :l". The series had some damn fantastic entrees that are ground breaking in the world of gaming; Super Metroid still is an amazing game, the Prime Trilogy is one of the best re-boots in gaming history and the original NES game alongside the GB/GBA games really show how timeless the series formula really is. I'm happy with those games, so I don't care what Nintendo does with the series going forward; it ended after Prime 3 for me and that's cool

.
Looking foward to Federation Force and hoping that Prime NX is fantastic

.