Who considers Mario Maker 2 a failure?

Edit: Beaten by Rol.

I was about to say, Mario Maker 2 sold nearly double the amount than the first game. I guess it has to do more with how poorly the Wii U sold compared to the Switch that Mario Maker 2 should've at least been 15 million+?

Mario Maker 2 didn't really reach it's full potential, but it certainly wasn't a failure.
It should be able to reach 9mil in the end.

I'm super surprised at how low Mario Maker 2 was sales wise. Don't get me wrong 8 Million isn't bad at all, but for a game that sold 4 Million on a 13M Wii U and with how much content and stuff this game had going for it I expected it to be one of the Switch's biggest sellers with at least 15+Million sold, but even NSMBU DX outsold it comfortably despite being far less ambitious of a game. I'm pretty sure Nintendo definitely expected more from Mario Maker 2 as well sales-wise.

I feel like Mario Maker 2 didn't do as well I guess cause consumers were uncertain about the game in general. Consumers may have thought that they had to make their own levels to play & maybe they didn't know they could play other people's levels. I also think that people probably were turned off on the idea that they had to look for good levels to play and didn't trust the levels other people made so they thought the safer purchase would be NSMBU since they know for certain that they're gonna get a good 2D Mario experience.

I could sort of relate too, IMO a lot of Mario Maker 2 levels do too much when it comes to the special effects and aren't very simple to pick up and play like NSMBU levels, of course you could find good levels in MM2 but that still takes more work than it should.

Yep which is probably the main reason why NSMBU DX outsold Mario Maker 2. Sakurai said in his recent video that "game essence" lowers "broad appeal" and I completely agree with him, this is a good example. Mario Maker is too complicated with multiple difficult skills, which allows for hardcore gamers to have a lot of fun, but not so much for the casual players which Nintendo has a lot of. Also creating something becomes very tiring and time consuming. Even Minecraft becomes overwhelming which results in people repeating RTAs or Battleroyales instead of creating a village or something.

Doesn't help that they released NSMBU DX only six months before SMM2. I don't consider SMM2 a failure, but I would've expected 10 million by now if I were predicting sales when the game first released. Either way, I do think it will be a 10 million seller eventually, but probably just barely.

It has two main factors. Lack of unity and lack of cohesion.

Mario 2d progression has one universe and one level design. 

Mario Maker doesn´t have this.

Second, professional content is better than amateur content. Amateur content needs to be a bonus, not the main meal of the games. A good example of extended live games was modding. Modding was complementary not the main dishes. When game go down the modders make game alive, sometimes making spin-off, likewise Dota and CS.  

A full fledge 2d Mario with AAA production with good competitive and cooperative modes will be a big success, plus one world creator ( and not only level designer creator). A full fledge world creator, with maps, with power-ups, will be a bigger success. 

Good idea, just combine mario maker with mainline mario + revive Mario 35/competitive mario + 3d mario creation + mario rpg creator + official rpg mario + garage builder mario edition + microtransaction for skins of different characters and design + required online access + increased NSO price + FREE demo + mario turns into villain + bowser marries peach + Miyamoto packaged with the game. I bet Nintendo don't have the guts to do this.

Failure perhaps wasn't the right word, probably more underwhelming or disappointing in sales. 

After the original game topped 4 million on the Wii U, a lot of folks expected a sequel on the vastly more successful Switch would blow passed 10 million, and when it didn't I saw a lot of folks saying it underperformed.

8 million is still a good figure for what it is, the way I see it.

A full fledge 2d AAA Mario 2d is good enough, but Nintendo maybe go crazy, who knows.