I've done some research into the development time of past smash games. 

Brawl was announced at e3 2005. At that point sakurai was not involved with the game. Development started around October 2005 and the game released in January 2008. Just a little over 2 years development.

http://m.ie.ign.com/articles/2005/11/16/smash-bros-revolution-director-revealed

Smash bros wiiu/3ds didn't start development until after kid icarus uprising which released March 2012. Those games released in September and November 2014 giving those 2 games about 2 1/2 years development. 

http://andriasang.com/comya5/

I'm not saying for a certainty that this is a new smash. But saying that they haven't had enough time to develop it just isn't true. If development started around 2016 that is in line with the development time of the past two games.

Interesting. Makes sense. This time they also have to develop only one version, and while Switch is definitely more powerful than Wii U, it’s not a mindblowing gap as like going from Wii to Wii U was.

They might even use the same engine and just tweak it.

The lack of a 3ds game likely has taken a decent amount of work out of the development.

Yup, many are saying it can't be a new game because, they haven't had enough time to develop it. The point of this thread is to show that this isn't the case. A lot of people seem to think that smash game take 6 years to make.

They've certainly had enough time to make a new game. I think we're looking at a Splatoon 2 style sequel - re-used the engine and assets (in some cases) but created new content.

At first this is what I thought it would be. But considering the short amount of time it took to make wiiu/3ds, I'm starting to think that everything might be new. It took them around 2.5 years to make 2 new smash games from the ground up.

That's not evidence. You want evidence? Look at the trailer.

-New logo
-Worked on with HAL Lab + dubbed as "original title"
-BOTW Link (this one is debatable, but it at least confirms it isn't a STRAIGHT port)
-New characters - the inklings, also confirms it isn't a straight port
-If this game was a port, we would've seen gameplay
-Sakurai said he was working on the game silently day by day. I don't think a port would require that much effort

The only thing that suggests it isn't a new game is the fact that they're planning to release a NEW smash in 2018. Unless they're going the melee route and are going to complete this game in a very short time, there's just no way they'd have enough time to make a polished Smash game that isn't somewhat reminiscent of Smash 4. We can definitely expect a lot of reused assets in this new title.

The whole point of this thread is to point out that this game has had enough time to be a completely new game. Brawl and Wiiu/3ds only had between 2 and 2.5 years of development. With the lack of a 3ds game this time, the devolpment should be shorter than last time.

If development started in 2016 and this game releases for the holidays this year then they should have had at least 2 years to make this game. That is in line with the development time for brawl and wiiu/3ds.

just give us ice climbers back now that we dont have the 3ds to hold us back

That's not evidence though. That's conjecture. There's no proof that Sakurai started developing the next Smash in 2016. He said he was silently working on it day by day, but he never said when he started to.