But the differnce is people dont question Nintendos abilities to make quality software.
Like right now people are legit scratching their heads and going "what is Xbox doing?".

The Wii U had huuuuuge game droughts, mainly due to lack of 3rd party support.
Though Nintendo had a few "head scratchers" too with the Wii U (Starfox Zero? Animal Crossing Amiibo festival?) and their 3D mario game was subpar (to my expectations after Mario Galaxy games)..... your right, Nintendo was "kinda" in a simular situation with the Wii U, sales where alot worse with the wii u, and people where ready to move on to the next system (thats not the "feeling" I get listening to xbox people though, and its worse for Xbox One X buyers, they expect more this gen and arnt ready to move on yet.).

I just think it'd be far smarter for MS to be conservative with the tail end of the X1 and focus on having a great system and lineup of first party titles for the next gen.

Nintendo isnt "unlike" the others, infact Id say when to announceing things down the pipe, their better than Microsoft is (this gen).
You "know" theres a SMT game, Octpath traveler, Smash, Bayonetta 3, Metroid Prime 4, in the works (this year or next).

With Microsoft you know nothing, after crackdown 3.

Pretty much this.

For Sony, it's the least critical for now, but a weak showing could negatively impact the rest of the PS4's life, so they can't slack off either.

Nintendo must deliver games. This year was pretty dry until now but there are a couple of games slated for this year we don't have a definitive release date yet (Yoshi, Fire Emblem, Smash), but those are not going to enough to push the console alone until next year, so a couple new games will have to come.

Microsoft recently announced bringing more first party titles, but at E3, they need to deliver no matter how far along those titles are (possibly just concepts at this point) to prove it. And not come with too much games-as-a-service bullcrap which could kill any good intent again.

Microsoft could really use a great E3 this year to keep Xbox sales from dropping.

Sony... yeah they're fine. The only thing I can see go wrong with them is lose a bit of reputation, because if they feel like they don't have to try as hard then they're at risk at "losing E3" in the eyes of the fans.

Nintendo I think with their current situation has biggest chance of doing well at E3. I mean look at how titles they have announced but not shown gameplay, a set release date or even a final logo/name; Yoshi, Fire Emblem, Pokemon, Metroid Prime 4, Bayonetta 3, Super Smash Brother. Add more unannounced stuff on top of that you've got one of the best Nintendo E3 showings. Nintendo are also the most unpredictable when it come to E3, so who knows what surprises they have in store. They always have  at least one big draw dropping moment. They only area I think they need to focus this E3 would be with some third party titles.

Well I don't get it they also have fortnite, at least 5 million sales  is not that bad and SoT/PUBG are review wise not great but sales wise they seem to be doing fine(great)

Sony of course. They're always dependant on E3 etc. Because they actually invest into their games/franchises. Thus, they need to promote them accordingly.

What has Microsoft that needs the concentrated attention of the gaming world? Exactly.

Nintendo? Haven't they become more reliant on their Direct Shows?

Well Nintendo is only one from all 3 that keeping they announcements much closer to release, so we really still don't know how Switch lineup for 2nd half of 2018. will look for sure. Saying that, if Nintendo is not going at all at E3, they would show their staff through Directs, so you can't really say they depending on E3, Sony and MS are more depending from E3 than Nintendo.

Clearly Nintendo. Kimishima himself said that the 2nd year was crucial. Switch is losing momentum as we can see in NPD or Media Create, so Nintendo needs to bring a more diverse line-up and prove that 3rd parties aren't just there for ports. They need to show a super-impressive Fire Emblem, a main Pokemon game (although I fear that the "go pikachu/evee" thing is a spin-off), and a Metroid Prime 4 that can rival Battlefield 5 and such.

If Sony has a strong E3 I'll be surprised. What more can Sony possibly have in store that we don't yet know about? Nintendo's E3 will be lauded if they only show a few things. If Nintendo shows a new Smash Bros. then that's all is needed. I'm not sure what Microsoft can do at this point to win people over. With all honesty I can't imagine how anyone can say X1 is in a better position than PS4 at the moment. And yes, there are folks out there who truly believe this.