“It’s true that the Nintendo Switch version is under development at this moment in time,” Okamoto told GameSpot. “Specifically with regards to the development, this game was developed on the Unreal Engine, but the version for Unreal Engine needs to be updated, I suppose, in order to support Switch. In that sense, the development is still expected to take a very long time. It’s still a long ways out.”

Hokuto made clear that the Switch version will definitely be released in the west, and that the while the team considered holding back the PlayStation 4 version to launch simultaneously with the Switch version, it ultimately decided against it.

https://gematsu.com/2018/04/dragon-quest-xi-for-switch-delay-due-to-outdated-unreal-engine-4

EDIT

Square Enix on why Dragon Quest XI was announced for Switch so early

“As we were working on Dragon Quest XI on Unreal Engine 4, we were also wanting to work on the Switch version, as well. Unfortunately, the engine was not compatible at first, though Nintendo and Epic were working on it together. When the engine revision released making porting to the Switch possible, we started working out our plans for the release.”

“We first announced the game before the Switch was even named the Switch, because we wanted fans to know we were working on that version. As the console started to come into focus, we found out that the engine and the console did not work together yet. Throughout development of the game, we worked with Epic and Nintendo to make progress to get the game on the Switch.”

https://nintendoeverything.com/square-enix-on-why-dragon-quest-xi-was-announced-for-switch-so-early-leaving-the-3ds-version-in-japan/

EDIT

Dragon Quest XI for Switch officially based on the PS4 version, won’t be censored in the west
https://nintendoeverything.com/dragon-quest-xi-for-switch-officially-based-on-the-ps4-version-wont-be-censored-in-the-west/

Man, it is somewhat depressing to think about the fact that the Switch blew away everyone's original expectations EXCEPT for when it comes to Japanese support. I mean, sure, there's a decent amount of games. But honestly it is not nearly as much as there probably should be. We probably won't see consistently good support to early 2019, and that might be too optimistic even. Either way, I'm getting YS Viii and I can wait on this title. Just sad that the people looking forward to it can't play it more immediately.

Scuks that compatibility seems to be the case for the delay, but it was a good choice not to hold out the PS4 version because of it.

Meanwhile, at Sudio Wild Card

https://youtu.be/6B6kJm5pOx8

Seriously, this should have been taken care of ages ago.  The UE4 Switch support updates went out over a YEAR AGO.  But here we have a plucky indie dev and their small time porting studio partner beating one of the wealthiest and most influential Japanese publishers to the punch with a game that gives the PS4 and Xbone a run for their money.  

This is a display of frankly hilariously sad incompetence.

So what he is saying is there won't be a Switch-version and now they are going drag it for eternity until nobody is asking for it anymore

I'm not trying to say I know much of anything on this topic, so apologies if I'm wrong. But don't you think it's a little ... ehh ... convenient ... that just about every time someone has an issue with a third party company on the Switch the conclusion is always incompetence? That seems to be the leap in logic made almost every time, and yet I don't think it's fair to make that conclusion about so many developers. The studio that develops Ark is far from small, and not only that, but they were developing a mobile port for who knows how long (probably before the Switch version, which makes it convenient to make a Switch port). I understand that Square Enix is bigger, but realistically speaking, they've already made most of their money off Dragon Quest; which unlike Ark Survival Evolved is not a "platform" title in the sense that it doesn't live on like Minecraft or Ark. It could even be that in reality, the amount of resources being located to Ark Survival Evolved on mobile and Switch is similar to that of a single Switch port for a triple A game like Dragon Quest. Not to mention Ark's developers are hardly praise worthy when it comes to stability and the Switch version will probably come out buggy, glitchy, and messy. I'm sure if the standards were the same you'd be getting Dragon Quest 11 a lot faster, too. 

I get the frustration and I'm probably wrong admittedly. But it just seems all too convenient to chock everything up to laziness or incompetence. 

That I highly doubt.  Dragon Quest has made too much money on Nintendo's handheld line and they are bringing over just about ever DQ spinoff so their intentions are clear.   I think this is just the final-fantasy-XV-development-hell, let's-make-a-trilogy-out-of-XIII, put-a-mobile-port-of-Chrono-Trigger-on-Steam side of Square.  The side that can be dumb as bricks and doesn't know how to business properly.

No

No, what he saying that game is definitely coming to Switch in West also, but not in near future.

It is NOT always my conclusion.  There are only 2 devs I give that one to.  Capcom and Square Enix with regards to this one game.  Oh and the team at 2K who brought over WWE.  I'm fully understanding of the issues and I don't expect Switch versions to pop out of the ground.  But this. Is. Ridiculous.

Here's the thing, I work in Unreal Engine 4, I know the kind of issues these updates bring and can tell you 1) no update I've seen has caused crippling issues that would necessitate a long, protracted fixing period, 2) whenever an update does cause a fuss, a follow up that fixes it comes within WEEKS, and 3) I would have heard about the Switch compatibility updates causing any major issues or necessitating big changes and no, they didn't.  Then there's the evidence that this line is BS.  Multiple Unreal Engine 4 games have come over and every dev has said the process of getting the foundations in is pretty painless.  Snake Pass is another prominent example of this.  Square has had dev kits from what we can gather for ages.  Since before the Switch launched.  Studio Wild Card didn't get a dev kit and set Abstraction Games on the port until mere months prior to GDC.  The fact Ark has a presentable build, be it alpha or not, and Dragon Quest XI doesn't even have a *screenshot* is laughable.  And yes, exactly, ARK is a major pain on systems much stronger than the Switch.  So why is Dragon Quest XI, a much cleaner game that is much lighter on the hardware, not even in alpha.  I mean, the way he talks about it it sounds like the Switch version hasn't even started since updating UE4 would be near step 1 so what on earth have they been doing for over 12 months?  Twiddling their thumbs?